Sum, if I were to put my boat in the salt down here for three months, I'd put the bottom paint on. I don't think I'd put on the barrier coat though especially if there were no sign of blisters. Multiple blistering would be a different story altogether. I've had five sailboats in the past and four of them stayed in the salt all the time and one was a Mac 25. Never a blister on the Mac. One blister on a Cape Dory 25, Multiple blisters on only one side of a Chrysler 26, never a blister on a "69 Pearson Wanderer. On the Cape Dory and Pearson I let the tide go out and painted one side, leaned her over on the following outgoing tide and painted the other side. Used Trinidad. It dried so fast it worked between tides. Found one blister on the Cape Dory, dug it out, stuffed a cotex in it and dried it out quick and filled it with Marine tex and painted it before the tide came in. Never a problem afterward. None of the boats ever had a barrier coat although the Chrysler obviously needed one. To do it absolutely by the book go for your barrier coat and the the antifouling paint. You're a by the book kind of guy and I respect you for it. I change my impellers every 4 years if I remember. I've got a '97 Nissan that's used to that and dosen't seem to care and is still using the same impeller housing. I know you'll do your best by your boat and whatever you do will be the right decision.
The photo is of my '69 Pearson Wanderer 30 footer drying out at low tide in front of the Shell Point Restaurant, Shell Point, FL in 1991 getting ready for a coat of Trinidad. Oddly enough the lone palm tree and my mast are in so complete parallel the lines coul run on forever and not touch. Those were the days! Gone forever.
