Announce new list of fallback directory mirrors in 0.3.1
The rebuilt list of fallbacks in #21564 (moved) was merged into 0.3.1 (and backported to 0.2.8 onwards).
I should send an email to tor-relays about this very soon.
I used to BCC all the operators, but I'm not sure if that's worth the effort any more. Now we have a 90 day stability requirement, I think I just want to do a quick rebuild every release.
To avoid a mass mail-out of operators before the next rebuild, I'll add a note to the announcement saying: "want to be on this list next time? email me with your relay fingerprint and I will put your relay on the list of potential fallbacks".