They should not have "Fright" Fest in 2013 and start thier off season after Labor Day, or they could have "Fright" Fest on Saturdays only if the park's fall attendance is low and fewer people go to theme parks in the northeast in the fall.
^ The water rides are closed for the season, but all the dry rides in the front ( Corn Popper, UFO, Sleigh Ride, Ranger, and Mind Eraser) were closed during past Fright Fests. With Rowdy's Ridge, I don't think that would no longer be the case for this year and future Fright Fests (if there's going to be anymore Halloween events at Darien Lake in 2013-beyond).
^ Shipwreck Falls is getting old as with any ride that over ten years old its reliabilty is going downhill so expect to see Shipwreck Falls closed more often or SBNO in 2013. At least Thunder Rapids and Grizzly Run are more reilable than Shipwreck Falls. I wouldn't surprised if Darien Lake replaces Shipwreck Falls with a new ride in 2014!
^ This past season they opened Shipwreck Falls late and it might just happen again in 2013 or they might end leaving SBNO and remove it in 2014 due low ridership this past season!
As for Thunder Rapids, the ride isn't going anywhere anytime soon, but sometime in the future it they would get rid of it for something new.
^ It's been over a decade since Darien Lake has gotten a "thrill" flat ride. But on an unrealted, note I predict the next ride to leave Darien Lake would be Shipwreck Falls!
I have very little info about Thrillbilly other than it was a Huss Troika ride and it was removed sometime before the 1990 season and I have yet to find any pictures of it!