After investigating the route which they took out of Barcelona, I have deduced that the airways they would have planned from LEBL to EDDL is via UN870 and UT853/T853.
The turning points along these airways, I assume are LEBL - DIBER SOSUR ROTIS MAXIR LUSOL IRMAR MOLUS PENDU IXILU GIVOR SORAL DIK ARCKY NOR - EDDL
Of course 4U 9525 never got any further than MAXIR, but it is after the waypoint ROTIS that interests me.
The track from ROTIS to MAXIR is 043. If this was infact in the FMGS flight plan, and the aircraft was in managed NAV mode for lateral navigation when it crashed, then it would have stayed on this track during its descent.
But if you look at the track from FD24, it's final track was actually 026. That is, it turned 17 degrees to the left from its assumed FMGS flight plan track, that's if the airways they intended to take is the one I have above.
This turn happened before top of descent (according to FD24 raw data published elsewhere). Wouldn't such a turn off track (pull selected mode) be consistent with memory item procedures for an emergency descent?