I have my organisation spam filtering all set to "quarantine", apart from my blacklist, and until now I always see at least a few dozen spam emails a day (mostly SPF) in quarantine, which I review every day or two to let through any false positives before deleting the rest.

However, a few days ago this suddenly changed, and now I'm getting virtually nothing at all in the quarantine, apart from the odd DNSBL. I know, I shouldn't complain about NOT getting spam! But I'm worried that something drastic has happened or there's a problem in the spam filtering, although I'm not aware of any problems receiving legitimate emails.

I've double checked and all my filters apart from the blacklist are set to "quarantine". The only thing I can think of is that around the same time this started, I added the Zoho admin control panel to my browser home pages and set it to "stay logged in" so I'm reminded to check them and don't have to keep logging in again every time I restart my browser or PC - but I don't see how that could be preventing the spam. Just in case, I've tried explicitly logging out of Zoho before exiting my browser, but that hasn't made any difference, I still almost always see "No Quarantine Messages are available."

Has anyone else noticed this? Perhaps Zoho have added the main spam domains to their DNSBL, but then I'd still expect to see them in the quarantine. Or maybe some major spam networks have been brought down?

PS my blacklist IS set to "reject", but I only have a handful of addresses and domains in it which I haven't changed for quite a while, and I don't have anything at all in the blacklist TLD section, so don't think that's the problem.