Prop,
I don't think so, but what I would do was call the day prior to my last day of reserve when they were assigning short call (AM Atlanta time) for my last day and ask for the 0300 or 0500 short call. Usually I would get it, but not always. If I got the 0300 I would call at 1200 or 1300 depending on my desired flight and ask to be released, once again I usually was accomodated.

Scoop