Do I have to decide at the time I enroll in DROP how long I will participate and keep working for the city?

Yes. However, for purposes of preserving maximum flexibility, many individuals may find it advantageous to elect to participate for the maximum period of time even if they feel that their actual period of DROP participation may, in all likelihood, end at an earlier date. You can always terminate employment and retire prior to the end of your announced DROP participation period; however, once announced, you are not permitted to work beyond your originally stipulated DROP ending date even if such date fell short of the maximum period allowed for DROP participants.