They are spammers they spam every 2minutes up to an hour. What I did myself was send 2 messages a day with almost a 12 hour difference. That's not spam dude so yeah I blame the manual add or auto by rules. If you need help with defining rules how about we come up with something like Same message in a 10 minute span 3 times in a row. Because once every 8-12 hours isn't spam. There's plenty of time for messages in between that & there is messages inbetween that if you're not seeing them then sither your filter's blocked them or amethyst chat is really that dead like nostr is dead because I see more global chat by bots then actual people.