I would recommend more rest. Doing the full Ascent 12 days out is pretty intense. I don't have a lot of Ascent experience to draw on, so I don't know what a perfect taper is. I had a good race in 2014 with more tapering, and a terrible race last year where I didn't do enough tapering. This year, I'm trying to make sure I don't overdo it again, and I feel really good right now. Three weeks out (July 31st), I did the entire course from Memorial Park to the summit. This past Sunday, I ran from Memorial Park to the Bottomless Pit sign. Saturday my plan is to run to Barr Camp. I am still doing an intense midweek hill workout every week, but with less distance/time. Other than that, I have been cutting my easy runs back quite a bit to reduce my total volume.
I wouldn't worry about losing the altitude gains from the last 7 weeks. From what I understand, you do not really gain anything by spending a couple of hours working out at high altitude. Whatever you do gain from it, you lose very quickly. I don't want to upset the people who like to do 3-2-1's, but from an acclimatization perspective, I think running above treeline is a waste of time. I think there are benefits to spending time above treeline, but having more red blood cells on race day is not one of them.