Ossia at the first line of a PianoStaff

[Knute Snortum]

I have another problem that I'd love help with.  (Sorry for all the
questions lately.)

The piece of music I'm working on is a piano piece with several ossia
bars.  I've been researching how to do this and I've come across a
problem I can't fix.  If the ossia bar is the first bar of a new line,
the PianoStaff brace and bar span are attached.  In the middle of the
staff all is fine.

I've attached the code to produce the problem and an image of what it
produces.  Any help would be greatly appreciated.

--
Knute Snortum

\version "2.22.1"

ossia = \markup \small \italic "ossia"

<<
  \new PianoStaff <<
    \new Staff = "ossia" \with {
      alignAboveContext = "upper"
      \remove "Time_signature_engraver"
      \hide Clef
      \hide BarLine
      \override BarLine.allow-span-bar = ##f
      \override KeySignature.stencil = ##f
      \magnifyStaff #2/3
    }
    { \stopStaff s1*6 }
    
    \new Staff = "upper" \relative {
      \key c \minor
      c'4 b c2
      <<
        { ees4 f ees2 }
        \context Staff = "ossia" {
          \key c \minor
          \startStaff ees4^\ossia g8 f ees2*1/2 \stopStaff
        }
      >>
      g4 aes g2 % \break
      c4 b c2 \break
      <<
        { g4 aes g2 }
        \context Staff = "ossia" {
          \key c \minor
          \startStaff g4 ees8 f g2*1/2 \stopStaff
        }
      >>
      ees4 d c2
    }
    
    \new Staff = "lower" \relative {
      \key c \minor
      \repeat unfold 24 { \clef bass c4 }
    }
  >>
>>