If our investment doubles before our time limit ends, we can withdraw some money from our investment and enjoy it. But even if our time limit ends, selling our entire holdings would not be the right decision. Because I think the price of Bitcoin is still in its infancy. The price of Bitcoin can increase a lot in the future. So if you sell your entire holdings because your time limit has expired, you may regret it later. So it would be best to withdraw the amount you need and keep the rest of the holdings.
I don't know if this your idea of taking profits before reaching your bitcoin goal because you see that your bitcoin portfolio has doubled. If you take profits, it will affect the growth of your portfolio to a better height compared to when you didn't take profit. Imagine that profits that you took will depreciates your portfolio and the profits should have generated more profits overtime.
If you start taking profits because your bitcoin portfolio has doubled from the initial amount that you put in, it can be tempting and before you know it, you might take profits again the second time killing your long-term accumulation goal and will delay you from reaching your bitcoin target. Let's not be profit cautious but focus on reaching our bitcoin goal since the profit is still there.