I try to get it in sometime in Feb. My shop gets slammed before Spring Break, so starting mid March things get busy.
Since DS is in May, it might be later this year since my calendar will not allow any trips before that (only possible trip is Havasu Boat Show).
Who cares as long as it gets done? End of a season, beginning of a season, mid season. I'd venture between Nov and Mar would be the fastest and cheapest since boat shops are not typically busy.
I'll get the drive alignment and impeller done at a shop whenever it is time, do all the rest myself. Eventually I will probably do that too. It gets done when it needs to, not based on a calendar schedule. I also don't boat seasonally, with the lake in view of the house, I can't stay off the water for too long.
I'm boatless for the first time in 30 years but always serviced after the first of Jan. Freeze was never a factor so I always took advantage of the winter specials like Absolute always offered. Man I can't believe how much money I'm not spending on my boating hobby.