Yes that is strange, what BIOS version did you update from, not that it should matter.
Version 2.80 is just the download server for the Internet flash server, which all ASRock boards with this feature have a similar update.
I've had a vaguely similar problem with the ASRock Restart to UEFI program, just seemed to break one day, no reason I could find.
A small chance this might help, did you notice that the ASRock XFast RAM program, which is installed with AXTU, is a separate program that does not uninstall when AXTU is uninstalled? Did you happen to use XFast RAM?
Either way try uninstalling AXTU, and then uninstall XFast RAM. Reboot and install AXTU again, which will install both again. IMO, stay with the version of AXTU on your board's download page, there are reasons for doing that since all versions may not support all boards.