After an interview with my boss, and much toing and froing between him and the deskie, I think that I have escaped with my ORD intact. However, I suspect that this is only the case because of the conversations that I had with the previous deskie about my decision to leave a little while ago.
I still think that this policy is fraught with problems.
Assumption is the mother of all funk ups.
So, advice to all who have a 16/38 (ORD) point (mainly promotees) keep a very keen eye on the calendar, and make sure that the deskie knows that you wish to leave in plenty of time. Moreover, fax it or keep a copy, and send it recorded. Maybe one day JPA will allow this feature, but I would not hold me breath.