We have an automated system that sends updates via email. That's fine, and for me it is useful information. I'd prefer to only see the most recent update, and have the rest trashed. That is, given the following list

I'd only want the selected version of 34022's update to remain in my folder. I've dug around in Rules, but nothing seems to fit the bill.
Is there a way to (automatically) delete the ones I don't want?