I don't think that a reverse DCA method is the best approach to profit taking. You seem to have a fixed price when you want to start taking profits. Why not just take all the profit you want to have and enjoy it? Spreading out your coin selling over a longer period of time implies that you expect a still rising price of which you want to participate. Why not keep your coins longer than? The thing with reach new ATHs is that many people want to take profits. Especially with a new milestone like 100k I would expect many people to sell some, which should lead to falling prices in the week afterwards.