Sorry, I should try and be a little more specific when posting the descriptions.
In your UBB Control Panel, if you go to "Members" - "Email Members", and continue from there, you'll get to these changes applied by my mod.
And... it enables you to create a list of email addresses for your members, which you can filter by last post date (on/before/after).
Have another look in there, and tell me that you don't see it.