You unfortunately have to grin a bear it on that 9th hour. The exact reverse of this is in the spring when you push the clocks ahead and you get that "Free" hour and only work seven. In the end it balances out. Happens to me every year.
I understand the concept of being paid by the hour, I was speaking from the perspective of someone who is assigned to the 11-7/12-8 shift. I don't agree w/ getting screwed out of that hours pay especially if it's on OT, but I would be curious to see how many Dept's out there pay their guys the 9 hrs in the fall and only the 7 in the spring. For me it balances out and anyone who takes that OT shift will get paid for the 8 weither you were there for 7 or 9hrs. Also I work a 4 & 2, so some weeks I only work 32hrs in a pay period, but I will still get paid for a 40hr week. So, I guess you could say that works to my advantage too right.
In an OT sense, I guess the best advise is to pay attention to what day it is so it doesn't happen again. It does suck that you get screwed out of that hour, I say it every year on that night. I am also excited in the spring when I only have to work 7hrs too. So, take that shift if it comes to you, a free hour of OT.