Thanks for that info. We’re going to try to salvage this mug. It is so good except for this terrible flaw.

This is a really good tear down. I’m curious, if I wanted to use a drill or something to attempt to disengage the retention mechanism, is there any way to tell where exactly one would want to drill a hole?

I can see the tab compared to some other objects in your pictures but I’m wondering if there is any visible reference from the outside that might make it possible.