[Rules] Assault hex recovery/retreat order

[richvalle]

If there are 2 dem platoons only in an assault hex and they try to recover and fail, is the 'recover, fail, retreat' process done for one before doing the process for the 2nd or are they considered simultaneous? 

This is in reference to the rule where units leaving an assault hex get a free shot at them. If it is one at a time then only the last unit fleeing gets the shot. If it's simultaneous it's both of them.