Moving figured bass extender lines

[Hyacinthe Besmoker]

Hello everyone! I am struggling with the placement of figured bass extender
lines. I would like to be able to move them up\down, but I can't figure out
how to do it. Here's a little snippet:

\version "2.24.4"

<<
\relative c' { \clef bass b, cis }

\new FiguredBass {
   \figuremode {
   <_>4 \bassFigureExtendersOn
   <_>4
  }
}
>>

If these were just normal figures, not extenders, "\override
BassFigure.extra-offset" could be used to move them around easily, but it
doesn't work at all with extender lines...

Thanks in advance for your help!