I personally believe that a person starts to have more flexibility in regards to managing his holdings once he reaches overaccumulation status, and a person does not reach such status in order to fall out of it, but instead to stay in such overaccumulation status, so then he would be able to start to sell small amounts of BTC, but still staying in overaccumulation status.. so he might start with
price based sustainable withdrawal before he moves into time-based sustainable withdrawal, yet being in overaccumulatoin status provides options regarding how to mange BTC holdings and the extent to which to stop accumulating and/or to start to sell whether price based or time based.
You are actually right on that. the over accumulation status actually increases an investors economic flexibility. He no longer solely relies on growing his bitcoin holding for future, rather he now has enough or I'll say a significant amount of bitcoins and can exercise a better control over his financial future. During his stay in the over accumulation status, he literally aligns with the economic principle of sustainable withdrawals. He's more like a retired holder, so what ever amount he spends during this stage should be able to sustain him, and also keep his investments on the run.