how to put a validation in change assignment for managers to not forget updating projected end date

Summary:

currently in responsive UI we have autocomplete rule which doesnt allow managers to submit the process in change assignment without filling in projected end date , but somehow when we enabled redwood in termination we saw that managers were also getting that error for autocomplete rule in Termination redwood which shouldnt happen as in termination we dont have projected end date, so we want to disable the autocomplete rule at whole and put a validation in place for change assignment screen for manager to get an error when they dont fill in the projected end date , can anyone guide