No, it doesn't. I just called and asked the same question since we are staying for 12 days. Basically, they said you would have to buy the 10 day one and then another one or 2 day pass - which is ridiculous if you look at the prices!
Anyway, what they said was that you have 11 days to use those 10 days of ticket time. In other words, if you have the 10 day pass, but you take a day off to go to Sea World or do something else, then as long as you didn't use it to enter a park that day, you did not use up a day of your pass. They give you a one day "grace" period. So technically a 10 day pass could last you 11 days if you take a day off in there somewhere and don't use it at a park.
I was a little surprised by this because I find it hard to believe that there aren't a lot of people staying for more than 10 days!