I would never try Jay as a day trip. Too damned long, and you're trusting that the bus driver actually takes a nap while you're riding. You're talking about ten hours of road time...that's crazy! The CT Ski Council does these bus trips all the time, but usually just to Southern Vermont mountains. I've never taken one, but friends tell me lots of people are already hitting the Bloody Mary's and partying it up at 6:00 am. Good on them, but I'm not gonna be trapped on a bus with them for five hours!
We're driving up to Jay Peak (actually, Sutton, Quebec) on Wednesday. If we leave at 4:00 am, we'll still get a 1/2 lift ticket for that day included with our room. It also includes two full day tix, and Jay Peak tix...for $100/person per day PLUS it includes breakfast and dinner each day. I'd much rather do that than risk my life to some old tour bus driver. But that's just me.