Asus don't realize how negatively this has affected it's own customers. I got this on Saturday and wasted hours doing scans and trying to figure out what is was. This is the Saturday before Christmas after working all week and Friday night too. ...
The update showed up today in the MyASUS app on my laptop. I would imagine yours should show up soon and make your life a little easier. Hopefully no new issues show up.
Just keep letting it do it's thing and keep rebooting. Mine has done that before and finally came around. If it never comes around you can try unpugging it and hold the power button down for like 40 seconds and then power it on again.