They should be getting removed within an hour of removal. We used to actively run our "clean quarantine" routine all the time but it was kind of expensive, so we moved it to be on an hour timer. Are you seeing them get removed from SM after that amount of time?

We deleted from the file system. The interface should also notice that the files are gone. Deleting 10k+ emails from spam quarantine 200 items at a time is horrible. SM needs better administration for the spool. So we delete from the file system as it is far more efficient.

Though, I just tested again for my install, items deleted somewhat horribly slow from interface, file system no changes at all. All 5600 emails are still on disk.

Is there a debug id I can use Matt?

As long as your on the now current (Yesterday's) build they should be clearing out after an hour or so. We've got another task this week to have it grab a hashset of known files in the directory and compare for changes. This would allow us to check every couple seconds or minute for changes. This will give us the more reactive monitoring while changing the old behavior, allowing much more efficient monitoring of the file system. 

I am not on yesterday's build yet, I am on the previous build.

And what would be "yesterdays build" ? Spam is getting out of hand on the old SM, particularly as Cyren no longer wants to work at all.

Yesterday's build referred to 16.3.6841. Cyren was eh when we used it, MessageSniffer is also just as eh. I've been reporting the same emails to MessageSniffer (through their POP gathering worker) for months and months and months now. I dont think they actually monitor reported spam messages.

Cyren was amazing when it worked up until a month ago, it solved the deluge of spam we received, but now it filters virtually nothing at all, the difference in it's effectiveness is so vast there's no way it's an aggregate trend, it's definitely broken, the difference is 4 orders of magnitude and a bottom of zero which is an acceptable mortality trend for a meteor slamming into the planet, not for spam hosts altering their heuristics.