That's something extraordinary. They can refrain from using mined Bitcoin for quite a long time even though the Bitcoin price has reached a high price. It's possible that it's such a small amount of what they mine, that it's unthinkable to move or sell it. We see a lot of Bitcoin mining servers around the world, with big buildings. Logically, the mining tools they use are also very large, including many wallet addresses. So we conclude that, 50 Bitcoins is a small amount of what they mine.