Delete after N days filter: how can I tell which emails are affected?

Delete after N days filter: how can I tell which emails are affected?

Greetings,

I have a filter set up with two actions: move to a different folder, then delete the mail if it is older than 90 days old. I use this for low-priority mail, but sometimes I have a message that I want to keep. I then manually move it to a different folder. Will the messages I move manually still be deleted after 90 days? If so, how can I undo the filter on a particular message? And how can I tell if a message is queued to be deleted?

Thank you.