Okay.
I guess you have a question behind that statement? You can request an extension to the expiration date. It has been awhile since I've needed to do that, but I think it is something you do through the license manager.
The expiration date is based on the date you install it. It doesn't matter whether you've used it or not. If I recall, 7 days to start with, and 45 days once you extend it.
