Multi Measure Rests in Cadenzas

[Calvin Ransom]

I have a cadenza where Staff A rests while Staff B plays and after the cadenza 
Staff A comes back in.
In the below minimal example, there is an extra rest added above the note when 
Staff A comes back in. How do I get rid of this rest? If I use r1 instead of R1 
I don't have this issue (but I need to use R1 as my cadenzas are longer than a 
single measure)

%%%%% SNIPPET BEGINS %%%%%
\version "2.24.1"

\new ChoirStaff <<
  \new Staff         {
    a1
    R1
    a %why is there a rest above this note?
    a
  }
  \new Staff  {
    a1
    \break
    \cadenzaOn
    a
    \bar "|"
    \break
    \cadenzaOff
    a
    a
  }
>>

%%%%% SNIPPET ENDS %%%%%

Calvin Ransom

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