The point of dollar cost averaging is to take advantage of the greater volatility in your investment than exists in your money.

If Bitcoin becomes money, then at some point the dollar will be the "investment" that has greater volatility. However, you're not trying to build up that investment, but rather you're trying to wind it down.

I'm just not sure if dollar cost averaging is still the prudent strategy in that scenario. It would be analogous to selling a fixed number of stock shares every month, regardless of their prices.