So, I tried to create a sample app with the issue with 11.02 but it works. However, this is what I tried and I know it must be somewhere between version 10.01 and 10.29 and 11.02.
I reverted from 11.02 to 10.29 and experienced the same issue in my app where the AlphaHints show up in the upper left corner. Ok, so then I went back to my last known working version which was 10.01. This is working fine. In version 10.01, all my AlphaHints are working based on Mouse.CursorPos position. So, obviously, the changes made between 10.01 and 10.29 is affecting this behavior. Please keep in mind I made no code changes in my app. All I did was reverting back to 10.01.
I wish you could reproduce this error. I'm not sure what to do now since I can't upgrade to any new versions or try to recreate my entire main form from scratch and see if that helps.