if Buffett refused to buy brkb at 440ish, it was unlikely to visit 500ish by june 20Th 2025, hence I'm short calls on 80 % of my stock. I forgot Uncle Warren has no idea how to value his life's work.

But there is more than one reason he might not buy BRK stock! One reason is that he thinks it is "too expensive" but another reason is that he may think that OTHER things are also too expensive and might become less expensive soon and be prime opportunities to buy. What is most likely is that it is a combination of a bunch of things he may think:
1. He thinks Berkshire is too high to buy back right now.
2. He thinks everything is a bit too high.
3. He thinks everything might drop soon, but that other stuff he likes will drop more than Berkshire will drop.
4. He thinks getting 4+% while he waits is sufficient for now.
5. He thinks it is "fair" to leave a huge chunk of cash for his successor to deploy, to put his own imprint on the portfolio, and is planning on retiring sometime soon (when you are 94 1/2, it is by definition soon no matter what).
6. ?