Your current situation is:
1) Someone send you mail
2) Rspamd score email lets say 12
3) Rspamd enforce greylist rule bc 12 > 7 (bigger than threshold) so Postfix return to sender soft error “try it again later after X sec” about 300 sec usually
4) Usually sender wait some time and try to delivery once again because of soft error. How long it’s per sender
5) Sender retry to delivery
6) *Rspamd check if time passed, if yes 7) (if no back to 3))
7) Delivery to Junk because score 12
- Greylist check for combination IP,sender,recipient for example (read to end !) if it’s gmail it usually come from different IP so new combination back to 3) BUT gmail is pre-whitelisted so graylist is not trigged on gmails severs. So if sender use some kind of dynamic IP it’s possible you make 4,5,6,… rounds until combination check. It’s possible that this can take hours to pass grelist
In case you change threshold to 13 it’s like this
1) same
2) same
3) no greylist straight to Junk bc 12 !> 13 (lower than threshold)
Hope this make it clear. But it’s for all mails, so you will not greylist spamers,…