A220 MAN SPD selection after Final Flap selection.
 

Why change from FMS SPD to MAN SPD after final Flap selection?
Seems to be unnecessary button pushing on final approach and distracting Manual setting of VAC / VGA and SPD increase in Acceleration at MAA capture.

There have been cases (witnessed them myself) where FMS speed commanded speeds well below Vref. Hence the limitation to use MAN speed. If I remember correctly this behaviour appeared if the landing Vspeeds were net from the non-coupled side FMS. However I do not know if this still persists as I am no longer on the type.