Heya. Just noticed a chain validation failure then the website being down. Cert shows an expiry of Thu, 17 Nov 2022 03:16:10 GMT.
Experiencing the same issue. Hope it gets renewed soon, it is not terribly late though which is good.
http://web.archive.org/web/20221117051255/https://decoder.link/sslchecker/f-droid.org/443
/LE: Fixed