As Caskbill so often posts, the best way to understand use year is to make yourself a chart. We have an August use year so our chart looks like this:
2004 use year. Points good for stays 8/1/04 thru 7/31/05
2005 use year. Points good for stays 8/1/05 thru 7/31/06
2006 use year. Points good for stays 8/1/06 thru 7/31/07
2007 use year. Points good for stays 8/1/07 thru 7/31/08
2008 use year. Points good for stays 8/1/08 thru 7/31/09
etc.
You can make your own chart using your use year by following the pattern.
You may bank points one use year into the future. Thus 2004 points may be banked into the 2005 use year. 2005 points may be banked into the 2006 use year and etc. Once banked, the points must be used by the end of the "new" use year. If they are not used by then, they expire (i.e., they are forfeited).
Use year determines banking deadlines. You may bank up to 100% of the current use year's allotment if you do it by the end of the 6th month following your use year. If you have an August use year, you may bank all of your 2004 points, as long as you do it by January 31. (Count your use year month as 1). Continuing on, you can bank up to 50% of your current use year's allotment of points if you do if by the end of the 9th month following your use year - in the August use year example, that would be April 30. You may bank up to 25% of your current use year's allottment if you do it by the end of the 10th month - in the example, that would be May 31. You cannot bank any points at all in the last two months of your use year.
You cannot bank if MS is closed, so if your deadline falls on a weekend, call a few days ahead. There isn't any advantage to banking early in the use year (unless you are afraid you will forget, LOL). Banking is a "final" transaction. You cannot "unbank" points.
Banking is also a "cumulative transaction" and is based on your allotment for the year. For example (again using the August use year), let's say you have 300 points and banked 200 of them in early January. After January 31, you would NOT be able to bank anymore points from that use year, because you have already banked more than 50% (200/300 = 67%).
Another example - let's say you banked 100 of your 300 points in early January. In March, you would like to bank more. Since the 100% deadline has based, you would be working with the 50% deadline of April 30. As long as you call before April 30, you could bank up to 150 of your 300 points. Since you already have 100 banked, you could only bank 50 more (50 + 100)/300 = 50%).
Now let's talk about the only time use year really matters - and that is if you have to cancel a reservation for a stay late in your use year. If you rarely or never have to cancel, then use year matters not at all. USE YEAR HAS ABSOLUTELY NOTHING TO DO WITH WHEN YOU MAY MAKE A RESERVATION. That is always 11 months ahead of check out for your home resort and 7 months ahead of check out for other
DVC resorts.
(Others have already posted the info below, but I thought since use year questions come up often, I'd just include as much as I can in this post and save it for the future).
When you cancel a DVC reservation at least 31 days before it begins, the points are returned to your account with the same status they had when you made the reservation. Current use year points are still current year. If you used banked or borrowed points for the reservation, they are still banked or borrowed points. (Keep your chart in front of you as you read the explanation - it will help you to understand).
Let's say you made a reservation for 1/1/05 - 1/8/05 at a DVC resort. You used current year points. In the August use year example, you would be using points from your 2004 use year because January 2005 falls within your 2004 use year.
Now let's say that you cancel that reservation on 11/15/2004 (more than 30 days ahead of arrival) and cannot reschedule your trip until October 2005. You get the points back into your account. They are still 2004 use year points. Since you will not be able to use the points before the end of your 2004 use year (7/31/05) and since you have not passed your 100% banking deadline (1/31/05), you can simply bank all of the returned points into your 2005 use year. That means you now have until 7/31/06 to use the points.
Now let's use the same example, but this time let's say you have a February use year.
2004 use year. Points good for stays 2/1/2004 thru 1/31/2005
2005 use year. Points good for stays 2/1/2005 thru 1/31/2006
etc.
100% banking deadline is July 31.
50% banking deadline is October 31.
25 % banking deadline is November 30.
No banking permitted at all in December and January.
Your trip dates (1/1/2005 - 1/8/2005) are still within the 2004 use year and you would use points from your 2004 use year to book it. Again, let's say you canceled in November (more than 30 days ahead of arrival). If you could not reschedule your trip before the end of your use year (1/31/2005), some of the points from that reservation could be lost. You could bank up to 75 of the returned points (25% of your total allotment in the example) if you did it before November 30. But that assumes that you haven't banked any 2004 use year points before that. If your reservation used 100 points, you would forfeit 25 of them on 1/31/05.
In these examples, you can see that an August use year would be better than the February use year if you had to cancel a January stay.
Once again, use year is not the most important consideration when purchasing DVC. It only matters if you have to cancel a reservation that is for a stay in the last 4 or 5 months of your use year. Keep in mind that your preferred travel dates may change over the course of your membership - what is "perfect" for you now, may not be so perfect later.
HTH. It can take a while to really understand use year and all its nuances.
Best wishes -