OnCalendar=Sun *-*-1..7 1:00:00should be changed to OnCalendar=Sun *-*-* 1:00:00
I checked the old syntax from source below and apparently it is correct. See https://wiki.archlinux.org/title/Systemd/Timers. Maybe it is due to systemd 258~rc3-1 update. -- Eric Valette

