You pay for the option with points in the use year you would be in at the time. The only exception is when you would actually be 2 years ahead and don't have access to the use year in question, you then get to pick which use year to pay in, the current one or the next one. It one applies when you're a full 2 years ahead, say for a Feb use year, you'd have to be Feb 2009 or after for it to come into play. Few II options actually can be had 2 years out even though you can start looking that far out. Most are 12 months or just under. Marriott's are 18 months for fixed week option and 12 months for the rest though you can actually deposit at 13 months out if you have a reservation. The only II exchange I can think of that's a full 2 years out on the
DVC list is Kona Coast on the Big Island though I'm sure there are others.