Even on this board of old friends we might agree that today, brkb is suffering from a lack of demand. IF you are short the Dec calls, do you buy them back on this weakness OR wait until DEC 19 and hope they are out of the money aka worthless?

I don't think there is any "lack of demand". I think it is simple market meandering, that's something very common in December. People, especially traders, tend to slow down in December, and many take the second half of the month completely off. But for anyone who absolutely, positively, doesn't want their shares called away (for example to avoid 2025 tax consequences), then they should buy those calls back when they think it's an opportune time. Because like I said, December is sometimes weird, one day before expiry there could be an unexplained pop in the stock price, and suddenly "worthless" turns into "assigned".

I've been buying back some old put options that will expire worthless on Jan 16th or thereabouts. But not because I am worried that they will be assigned (there is a much less than 1% chance of that happening), but rather because I want the capital gain to be accrued in 2025 rather than in 2026. So I have standing orders to buy them at a penny, and every so often some of them execute. If they don't all close by the end of the year, I'll have to raise my bid to 2 cents.