I’ve run the calendar cleanup a few times and never looked. Today I was looking in a new (to me) view and saw this:
These items should have all been deleted as they are ancient history (I had checked to clean anything older than 6 months and these are)
Subject: How cleanup window is identified
Calendar cleanup deletes documents based on ‘last modified’ date. In your case, the calendar entries will only be removed when the date of the calendar entry and the last modification are both more than six months ago. Also, this rule applies to any document associated with the invitation, so if one instance of a repeating meeting has been modified, updated, responded to, etc. within the last six months, all instances of that invitation will be preserved.
It appears that is the case with these documents from the screenshot, but could you please confirm? Could you also check that the $NoPurge dates on these docs (via the properties dialog) are also more than six months in the past. And the next thing to check is that all these dates are also at least six months prior for all documents associated with the calendar entries in question.