I've perused FT, but I the most recent post I've found on FB mileage expiration was more than a year ago, so:

I have about 280,000 FB miles in my account, deposted from Chase, Citi and Amex from as far back as early 2020. They were to be for mileage trips in 2020 and 2022, but in both cases I had to cancel them due to Covid.

My questions:

1. I believe that FB extended expiration dates through Dec. 31, 2022. Does that mean that the two-year expiration clock starts ticking now, so that I have the miles through 2024, or that my 2020 transfers into FB are in danger of expiring very soon?
2. Am I correct in assuming that if I transfer any points into my FB account from Amex, Citi and Chase, all of my miles will be extended for two years? (All of the miles are from transfers, not flights.)
3. If the answer to #2 is yes, may I simply transfer from any one of those credit cares, or must I transfer from all three?
4. Above and beyond credit card transfers, am I correct in understanding that the only ways to extend the mileage expiration date are by:
a) flying Air France, KLM or one of their eligible airline partners,
b) having an elite status, or
c) spending on the Air France credit card?

Thanks for any help with this.