Better antispam filtering?

Runbox 7 Runbox 7 Webmail
#1

Hi,

I was added to my sports club contact email address that redirects to my Runbox mailbox.
As this email is pretty exposed, I’ve been receiving significantly more spam than before. The problem is that several of these spam are not detected by Runbox and lands directly in my inbox.
Some are even obvious phishing.

Until now I’ve been running Runbox with default spam filter settings
But I notice “Use trainable spam filter” is available as well as “Advanced: Reject if possible”

I consider enabling those 2 but it raise a few questions:

  1. Does training work only through Runbox webmail based on spam/not spam button?
    or also when moving emails via IMAP from a third-party client like Thunderbird on Android?
  2. Does moving a mail into the Spam folder count as a spam training signal? And does moving one out of Spam back to the inbox count as a ham signal?
  3. Does redirected email (like my contact email redirected to my runbox email) affects Runbox spam assassin efficiency ?
  4. Regarding the “Advanced: Reject if possible” option: I understand it rejects instead of receive and move in spam folder — how aggressive is it really? Is it limited to obvious spam with very high scores, or is there a real risk of losing legitimate emails?
#2

I don’t have answers to your questions, but I do know they are working on figuring out why their spam filtering is so bad. I was forced to turn it off entirely as I was getting too many false positives. I use a local program on my tablet and computer, so perhaps if I did webmail it would be easier to handle. But, it is better for me to handle the spam locally. I do pre-scan my emails with MailWasher Pro from Firetrust to delete spam every morning.