StaffSymbol stops short of end-of-\score TimeSignature or KeySignature

[Daniel Rosen]

The following example shows two movements of a work which are to be performed 
without pause (imagine an "attacca" instruction at the end of the first \score 
block). My question: how can I get the StaffSymbol to continue through the 4/4 
marking at the end of the first \score (and through the key change at the end 
of the second), as it does through the 2/4 at the end of the line above?

This question is very similar to the one Harm responding to in this post from a 
couple of months ago: 
https://lists.gnu.org/archive/html/lilypond-user/2020-01/msg00541.html However, 
when his solution is applied here the results are still not quite right: when 
everything in my example is uncommented, the cautionary TimeSignatures are no 
longer vertically aligned because the 4/4 is pushed slightly to the left, 
there's a little too much space between the right edge of the TimeSignature and 
the end of the StaffSymbol, and the StaffSymbol itself stops just short of the 
right margin (I can't figure out a way to draw a vertical line that will show 
this latter point more clearly, but if you print it out and use a straight edge 
it'll be very apparent). 

%% Example begins
\version "2.20.0"

music = \repeat unfold 36 b'4

\book {
  \paper { print-all-headers = ##t }

  \score {
    \header { title = "I" }
    {
      %\override Staff.StaffSymbol.break-align-symbols =
      %#'(time-signature key-cancellation key-signature staff-bar 
break-alignment)
      \numericTimeSignature \time 3/4
      \music \time 2/4 \break
      \music \bar "||"
      %\tweak X-extent #'(0.25 . 2.4)
      \time 4/4
    }
  }

  \score {
    \header { title = "II" }
    { \numericTimeSignature \music \key b \major }
  }

}
%% Example ends
        
DR