Subject: Re: Europe/Sofia: midnight transitions 1983-1996 and the 1996 September end - primary sources and a patch
Paul, Tim, all,
Two updates to the patch I sent on 11 September, & the years before
1983. Corrected patch attached; it applies to tzdata2026c and compiles.
1. 1989 and 1995. The rule line
Rule Bulg 1983 1996 - Sep Sat>=24 24:00 0 -
returns the clocks on 30 September in those two years. The acts say the
24th:
- Decision 394 of 1995-09-22 (State Gazette 88/1995) repealed the
30 September date of Decision 118/1995 and set "24:00 on 23 September
1995, Saturday". Text on the Council of Ministers' legal system:
https://pris.government.bg/document/ec66a2eaa8ac98101b12cb7bb9739bbe
- For 1989 the March notice I quoted announced 30 September. A Council
of Ministers letter of 1989-09-04 (register title "the return to
astronomical time 24/09/89", pris.government.bg document
b90e662e34f86a98770924d54326075e) moved it, and the BTA notice printed
on 1989-09-05 and again on 1989-09-21 in Rabotnichesko Delo (nos. 248
and 264), Trud, Narodna Mladezh, Zemedelsko Zname, Kooperativno Selo
and Narodna Armiya reads: "The return to astronomical time in the
People's Republic of Bulgaria for 1989 will be on 24 September,
Sunday, at 0:00 hours." The sunrise table in Rabotnichesko Delo of
1989-09-27 (06:19/18:15 for Sofia) is already in standard time; the
same table on the 23rd (07:15/19:23) is summer time.
The autumn rule is therefore the last Sunday of September at 00:00 -
the E-Eur instant - for 1983 through 1995, and 29 September in 1996:
Rule Bulg 1980 1996 - Sep lastSun 0:00 0 -
2. 1979-1982. The file's 23:00 springs, 01:00/02:00/03:00 autumns and
Monday 29 September 1980 have no Bulgarian source. The notices of those
years are all midnight:
1979 Decree 6/1979: "from 0:00 on 1 April" forward, back "on
1 October"; railway notice, Rabotnichesko Delo 1979-03-30: "the
new time from 00:00 on 1 April"; Narodna Mladezh 1979-09-27:
"winter time from 0:00".
1980 BTA, 1 April 1980 (Rabotnichesko Delo, Trud, Narodna Mladezh,
Narodna Armiya, Kooperativno Selo): "from 00:00 on 6 April,
Sunday, to 24:00 on 27 September, Saturday".
1981 Otechestven Front 1981-04-04: "on 4 April at midnight the clocks
will already show 1 ... on 26 September, Saturday, when at
midnight the clocks will be put back"; 1981-09-25: "on
26 September at 24:00".
1982 Otechestven Front 1982-04-02: "on Saturday night, 3 to 4 April";
Narodna Mladezh 1982-09-23: "winter time from 24:00 on
25 September 1982".
First Sunday of April at 00:00, eve of the last Sunday of September at
24:00:
Rule Bulg 1979 only - Apr 1 0:00 1:00 S
Rule Bulg 1979 only - Oct 1 0:00 0 -
Rule Bulg 1980 1982 - Apr Sun>=1 0:00 1:00 S
and the zone line's 1979 boundary becomes "1979 Apr 1 0:00". These are
read in the OCR full text of the Arcanum newspaper index
(adt.arcanum.com, Rabotnichesko Delo 1944-1989 and the other Sofia
dailies, from the RFE/RL collection at Blinken OSA); the page images
are behind its subscription. Several papers carry each notice.
The full chronology - every Europe/Sofia moment in the file from 1880 to
2026, what each Bulgarian document says, and the grade of what we hold -
is in the deposit and at https://oco.bg/tz/sofia. Rows before 1979
(1894, 1942, 1943-1944, 1945) are not changed: no Bulgarian source for
them has been read. From 1997 the EU rule stands: Decree 94/1997 is
still in force (the Bulgarian Institute of Metrology's notice for
29 March 2026 names it; the EU's transposition register lists it as
Bulgaria's only measure).
Two instruments are still on order from the Central State Archive: the
text of Directive 15/1980 (item 12 governed summer time 1980-1996) and
of Decision 196/1982 (the rule: last Sunday of March, last Saturday of
September). Neither is expected to move a transition - every date
1980-1996 is fixed by the yearly acts and notices above - but I will
send them when they arrive.
Against tzdata2026c the corrected patch moves 747 hours of Sofia time:
35 in 1979-1982, 40 in 1983-1990 (the hour, not the date) and 672 in
1996. Nothing outside 1979-1996 moves.
The deposit https://doi.org/10.5281/zenodo.22695588 now carries the
corrected patch, the acts, the September 1989 plates and the chronology
1880-2026.
Ivan Petrov Ivanov
Sofia, Bulgaria
https://astrocogy.com, https://oco.bg
On Fri, 11 Sept 2026 at 13:18, Ivan Petrov Ivanov <[email protected]>
wrote:
> Tim, all,
>
> Coming back to the Bulgarian archive work, and this time with the
> results.
>
> I have now read the originals for every transition in the disputed
> period at the National Library in Sofia. The short version is that the
> Bulgarian record is uniform and it disagrees with the database in the
> same direction every time: Bulgaria moved its clocks at midnight
> throughout 1983-1996, not at 02:00 or 03:00.
>
> I also have to correct something I wrote in my first message. I said we
> found no 1996 act. That was wrong, and the act exists: Council of
> Ministers Decision 205 of 14 March 1996, quoted by the government's own
> press office.
>
> WHAT THE SOURCES SAY
>
> The Bulgarian Telegraph Agency published a fixed notice before each
> transition in "Rabotnichesko Delo", the daily of record. The wording is
> almost identical for eight consecutive years, which is in itself the
> signature of a standing rule and not an annual decision. Every one of
> them says midnight:
>
> 1983-03-26 "summer time ... for 1983 will be introduced on 27 March,
> Sunday, at 00,00 hours ... the return to astronomical time
> will be on 24 September, Saturday, at 24,00 hours"
> 1983-09-25, p. 2 a report, not a notice: "At midnight, for the fifth
> year
> running, the hands of our clocks repeated the hour just
> past."
> 1984-03-25 "Today at 0,00 hours summer time began ... the return will
> be
> on 29 September, Saturday, at 24,00 hours"
> 1985-03-30, p. 6 spring 1985, and the autumn announced
> 1985-09-28, p. 6 autumn 1985
> 1986-03-29 30 March, Sunday, 00,00 / 27 September, Saturday, 24,00
> 1986-09-27 27 September 1986, Saturday, 24,00
> 1987-03-28 29 March, Sunday, 00,00 / 26 September, Saturday, 24,00
> 1987-09-26 26 September 1987, Saturday, 24,00
> 1988-03-26 27 March, Sunday, 00,00 / 24 September, Saturday, 24,00
> 1988-09-24, p. 2 24 September 1988, Saturday, 24,00
> 1989-03-25, no. 84 26 March, Sunday, 00,00 / 30 September, Saturday,
> 24,00
> 1990-03-24 25 March 1990, Sunday, 00,00
>
> That spans every year of the block the database currently runs on C-Eur
> (1983 through 1990) at both ends and in the middle. Not one notice says
> 02,00 or 03,00.
>
> ONE DETAIL THAT CHANGES THE RULE LINE
>
> The autumn transition is the last SATURDAY of September at 24:00. That
> lands on the last Sunday in most years, but not in 1989: the notice of
> 25 March 1989 puts the return at 24:00 on Saturday 30 September, which
> is 1 October 1989 00:00 - a week past the last Sunday of September. A
> rule written as "Sep lastSun" would be wrong in that year. "Sep Sat>=24
> 24:00" fits all eight years and 1996 as well.
>
> THE LEGAL SPINE
>
> Decree 6/1979 (State Gazette 12/1979, p. 115) introduced summer time,
> forwards from 0:00 on 1 April and back on 1 October.
>
> Decree 94/1997 (State Gazette 24/1997, p. 10) introduced the EU rules
> and, in its closing clause, repeals precisely two instruments: Decree
> 6/1979, and item 12 of Directive 15/1980, which the repealing text
> itself labels as never promulgated. Two acts, no third. So no Bulgarian
> instrument changed the transition hour in 1983, and none changed it back
> in 1991 - which is what the current data claims happened, twice,
> uncited.
>
> I have also photographed the annual index of the State Gazette for 1980.
> Directive 15/1980 is not listed in it, in keeping with the 1997 text
> calling it unpublished.
>
> I asked the Bulgarian State Archives Agency for the full text of both
> hidden acts. Its answer of 9 September 2026 (ref. ZDOI-00-34) is itself
> informative: the request falls outside the freedom-of-information act
> altogether, because that act excludes anything held in the National
> Archive Fund, and it was forwarded to the Central State Archive, where
> copies are a priced service rather than a right. So the texts are
> reachable, for a fee, on the archive's own timetable, and I will report
> them when they come. What can be established today is where they are
> not: not in the State Gazette, which is why the practice must be read
> from the newspapers, and why these plates exist.
>
> 1996
>
> Decision 205 of 14 March 1996 set the return at 24:00 on Saturday 28
> September 1996. It was announced by the Council of Ministers press
> office in "Duma", 27 September 1996, p. 1. Balkan Airlines advised
> passengers (Demokratsiya, 28 September 1996, p. 7) that its
> international flights would leave and arrive one hour earlier than
> printed, reckoned from 29 September to 26 October 1996 inclusive - which
> is precisely the interval during which Bulgaria stood one hour off
> Europe. The database's 27 October 1996 has no Bulgarian act underneath
> it.
>
> WHAT IS PROVEN HERE, AND WHAT I AM PUTTING ON RECORD AS STILL SUSPECT
>
> Proven, and carried by the patch: 1983 through 1996, midnight
> transitions, the 1996 non-alignment with the EU October end, and the
> legal spine holding them together.
>
> This is not the whole of the Bulgarian record, and I would sooner flag
> the areas I still doubt now, in the open, than have them turned up
> piecemeal later. Each of these I have looked at enough to distrust the
> current data, and not yet enough to replace it:
>
> * 1979-1982. These rule lines still hold Shanks-era hours - spring at
> 23:00,
> autumn by turns at 01:00, 02:00 and 03:00 across three consecutive years
> -
> and one transition, autumn 1980, is dated to a Monday, 29 September,
> where
> every other year in the file is a Sunday. Decree 6/1979 itself gives
> 0:00 on
> 1 April and 1 October, which by itself disagrees with the file's
> 1979-03-31
> 23:00. I do not have yet the newspaper notices for these four years. I
> am not
> patching them - but I do not believe they are right, and I would not
> want the
> 1983-1996 fix taken as an endorsement of the years just above it.
>
> * 1991-1995. I have no notices in hand for these five springs and
> autumns. The
> patch extends the midnight rule over them on the strength of the 1997
> decree's
> repeal clause, which lists the entire prior regime and names no
> intervening change, together with 1990 and 1996 observed at either end.
> That
> is a continuity argument, not five observations. If you would rather see
> the
> years cited directly first, I will go back for them - but the current
> C-Eur/E-Eur split across this span cites no primary source either, so the
> patch replaces an uncited guess with a reasoned one.
>
> * The wider region. If the Bulgarian pre-1997 record is wrong in this
> way, the
> neighbouring zones the file derives from Bulgaria are worth re-checking
> on the
> same kind of evidence. I am writing to you in a separate message about
> Europe/Bucharest
> and Europe/Chisinau; I mention it here only so the connection is on the
> record in
> this thread too.
>
> None of this dilutes what the patch changes. I state it because I would
> sooner have the maintainers hear the full shape of the problem from me,
> at the moment the first well-sourced part of it lands, than discover the
> rest afterwards. Please treat this message as the reference entry for
> the Bulgarian case, to be added to as the remaining archives open.
>
> THE PATCH AND THE PLATES
>
> The patch is at the foot of this message.
>
> The photographs are attached as a single PDF: 18 dates, 36 pages. Each
> date is a whole page carrying the masthead, the date and the page number
> in one frame, followed by the close-up of the notice itself, so every
> quotation above can be verified against the image it came from. The
> originals are unedited camera RAW files, kept and checksummed; the
> attached pages are the same frames in grayscale with the lighting
> flattened, nothing added or removed. They are published as well at
> https://astrocogy.com/tz/bulgaria, with the checksums of the untouched
> camera originals beside them.
>
> The same package is also deposited with a DOI: the plates, the index,
> the patch, this letter and the checksums, so all of it can be cited and
> retrieved without any website of mine.
>
> https://doi.org/10.5281/zenodo.22695589
>
> If it is accepted,* I would be happy to be credited as Ivan Petrov*
>
> *Ivanov, OCO, https://oco.bg <https://oco.bg>, https://astrocogy.com
> <https://astrocogy.com>*
> Ivan Petrov Ivanov Sofia, Bulgaria
> https://oco.bg, https://astrocogy.com
>
>
>
> --- a/europe
> +++ b/europe
> @@ -958,12 +958,42 @@
> # EET -> EETDST is in 03:00 Local time in last Sunday of March ...
> # EETDST -> EET is in 04:00 Local time in last Sunday of October
> #
> +# From Ivan Petrov Ivanov (2026-09-11):
> +# Primary sources read in the originals at the National Library, Sofia;
> +# photographs and transcriptions: https://astrocogy.com/tz/bulgaria
> +# archived with checksums, citable:
> https://doi.org/10.5281/zenodo.22695589
> +#
> +# Decree 6/1979 (State Gazette 12/1979, p. 115) introduced summer time,
> +# moving the clocks forward from 0:00 on 1 April and back on 1 October.
> +# Decree 94/1997 (State Gazette 24/1997, p. 10) introduced the EU rules
> +# (03:00/04:00, last Sundays of March and October) and repealed exactly
> +# two instruments: Decree 6/1979, and item 12 of Directive 15/1980, which
> +# is marked in the repealing text as never promulgated. No Bulgarian act
> +# changed the transition hour between 1980 and 1997.
> +#
> +# Bulgarian Telegraph Agency notices in Rabotnichesko Delo give the wall
> +# time for every transition from 1983 to 1990, and all of them are
> +# midnight - "at 00,00 hours" going forward, "on Saturday at 24,00 hours"
> +# coming back:
> +# 1983-03-26 (for Mar 27) 1983-09-25 p. 2 (report: "at midnight")
> +# 1984-03-25 ("today at 0,00") 1985-03-30 p. 6 1985-09-28 p. 6
> +# 1986-03-29 1986-09-27 1987-03-28 1987-09-26
> +# 1988-03-26 1988-09-24 p. 2 1989-03-25 no. 84 1990-03-24
> +#
> +# The autumn transition is the last SATURDAY of September at 24:00, which
> +# is usually but not always the last Sunday: in 1989 the notice of
> +# 1989-03-25 sets the return at 24:00 on Saturday 30 September, i.e.
> +# 1989-10-01 00:00, a week after the last Sunday of September.
> +#
> +# In 1996 Bulgaria did not follow the EU October end. Council of
> +# Ministers Decision 205 of 1996-03-14, announced by the government press
> +# office in Duma (1996-09-27, p. 1), returned the clocks at 24:00 on
> +# Saturday 1996-09-28; Balkan Airlines (Demokratsiya, 1996-09-28, p. 7)
> +# counted the resulting one-hour offset against Europe from 1996-09-29 to
> +# 1996-10-26 inclusive.
> +#
> # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
> Rule Bulg 1979 only - Mar 31 23:00 1:00 S
> Rule Bulg 1979 only - Oct 1 1:00 0 -
> Rule Bulg 1980 1982 - Apr Sat>=1 23:00 1:00 S
> Rule Bulg 1980 only - Sep 29 1:00 0 -
> Rule Bulg 1981 only - Sep 27 2:00 0 -
> +Rule Bulg 1982 only - Sep 26 3:00 0 -
> +Rule Bulg 1983 1996 - Mar lastSun 0:00 1:00 S
> +Rule Bulg 1983 1996 - Sep Sat>=24 24:00 0 -
> # Zone NAME STDOFF RULES FORMAT [UNTIL]
> Zone Europe/Sofia 1:33:16 - LMT 1880
> 1:56:56 - IMT 1894 Nov 30 # Istanbul MT?
> @@ -971,9 +1001,7 @@
> 1:00 C-Eur CE%sT 1945
> 1:00 - CET 1945 Apr 2 3:00
> 2:00 - EET 1979 Mar 31 23:00
> - 2:00 Bulg EE%sT 1982 Sep 26 3:00
> - 2:00 C-Eur EE%sT 1991
> - 2:00 E-Eur EE%sT 1997
> + 2:00 Bulg EE%sT 1997
> 2:00 EU EE%sT
>
> # Cyprus
>
europe-sofia-1983-1996.patch
Description: Binary data
