Cody thanks for looping back around to post what you found.
I have run into a hand full off oddities when moving from BIOS to UEFI but not noticed that one but enough oddities that I don't recomend BIOS to UEFI conversion. It sounds like it wasn't an intentional conversion and in the end you are avoiding the oddities by going UEFI to UEFI.
Good work identifying where the behavior was coming from and resolving it.
Cheers.