[PontifexMinimus]

Then unsubscribe from that blocklist.

[agoodusername63]

Does that unblock whoever got blocked by the rogue blocklist?

[wlonkly]

Yes, your combined blocklist is point-in-time. If you unsubscribe from a blocklist, a user on that blocklist will be immediately unblocked, provided they're not also on another blocklist you subscribe to (and that you didn't block them directly).

(Outside of eventual consistency, of course.)