I recently upgraded to a new Mac, and am running the newest version of Mojave. I was running Mojave of my former setup as well. I am using version 2.9.35 of Spamsieve. I have several email accounts all using IMAP.
On the new Mac Spamsieve seems to be working fine, but does not update back to the IMAP server until my Mac wakes up. In other words, I get lots of spam on my iPhone, unless I wake up my Mac and give it a minute to sync the email/spam updates. This was not the case with my prior setup.
Any ideas how I can get my email to update even when my Mac is sleeping or locked?