Make yourself a Use Year Chart for your particular UY. An Aug UY chart looks like this:
Use Year.....Vacation dates included for this UY
2005.....Aug 1, 2005 through July 31, 2006
2006.....Aug 1, 2006 through July 31, 2007
2007.....Aug 1, 2007 through July 31, 2008
2008.....Aug 1, 2008 through July 31, 2009
2009.....Aug 1, 2009 through July 31, 2010
2010.....Aug 1, 2010 through July 31, 2011
and so on
Looking at the dates, you can see that Oct 2007 falls within your 2007 UY, so that vacation requires 2007 points.
You can have points in 2007 three ways: (1) your regular 2007 allocation, (2) banked 2006 points, (3) borrowed 2008 points.
Assuming you have a 150 point contract and have no 2005 points, and want to use all 150 of your 2006 points for your Oct 2007 trip, then you need to bank your 2006 points. You have until Jan 31, 2007 to bank 100% of your 2006 points.
However, since you are planning on making the reservation in Nov '06, you can do everything with one telephone call that month. Tell MS you want to make your reservation and will be banking your 2006 points. They will bank and use your 150 2006 points, and will use your regular allocation of 2007 points, (as many as needed), and if additionally needed, will borrow any 2008 points required to complete the reservation.
They will only borrow as many points as actually needed to make the reservation.
Using banking, borrowing, and regular allocation points, you will have up to 450 points available for your Oct 2007 vacation.