The easiest way for me to remember things is to first decide UY that you want to travel. Once you know that, you can then figure the rest out. Any vacation can be paid for using banked UY points from the previous UY, current UY, and borrow from the next.
Since your Feb 2012 will happen in your 2011 UY, you can "pay" for it with banked 2010 points, 2011 points, and borrowed 2012 points.
Have fun!