From the PWA: A pilot who is in the last 12 months of such category freeze may be awarded an AE or VD to another base for which qualification training is required if he is unable to be awarded an AE or VD to such base in his current position in a given posting. In such event, the balance of his existing category freeze will be added to the category freeze resulting from the new position award.

So can't even bid until your 12 month point, but then depending on the length of the AE conversion window, could be another 6 to 12 months until you finally convert.