Well, it is a bug and not a bug.
The homing speed is always correct, only the displayed speed is not correct, but it works with the correct speed always.
The speed is not always correctly displayed, because in a master-slave homing sequence the axes are slaved and unslaved at some points when the gantry is squared and calculating the speed in all cases is not done correctly.
We will fix this later as it is not an urgent to get fixed issue because only the speed displaying is incorrect.