Immediately after pushback, the chocks are shown as removed in the aircraft status (MCDU -> Options -> Ext Controls), but in fact they are not. The only way I have found to get the aircraft rolling is to first “set” the chocks, then remove them again. This seems to toggle them into the correct state that also matches the status shown in the aircraft. Otherwise it is impossible to move the aircraft short of applying massive thrust (and then lurching off the ramp area and into the grass).
