Not clear what you are asking so answer may be determined from the following:
Assume Sep use year:
For trip that occurs between Sep 1, 2011 and Aug 31, 2012, the current use year points for that trip are ones coming in Sep 2011. If you have points from your Sep 2010 use year allotment, you can use those for a trip between Sep 1, 2011 and Aug 31, 2012 only if you bank them into the Sep 2011 use year. If you have right now points that were banked into your Sep 2010 to Aug 31, 2011 use year from Sep 2009 use year, those can be used only for a trip that ends on or before Aug 31, 2011 because banked points cannot be banked into a second use year..
As far as calling to reserve, use year is irrelevant, you can always call 11 months out for home resort and 7 at others. Points that you actually use for the trip and whether you need to bank, are determined by when you will you be at WDW not when you call to reserve