I’ve contacted Apple about this without a good answer, so I thought I’d post this here and see if anyone else was facing this issue…
Since I installed Catalina (I do have the latest version of SpamSieve running prior to the upgrade), my rules started working only some of the time. After trying some reindexing and other things, I finally took the step of deleting all rules and I’ve now started over.
The rules are working better but still, some messages are going to the folder I assigned in the rule but a copy is also kept in the inbox. I have the rules set to “move” and not “copy” so I’m not sure why. I see the SpamSieve rule, which I have first, sends all mail to the Spam folder first. I assume SpamSieve then takes over and sends mail back to the inbox after being filtered. If that’s how it works, then I can see how that might mess up Apple Mail’s rules potentially.
Again, I’m just checking to see if anyone else is facing this or not.
Thanks in advance!