The upgrade issue is now resolved.
However when upgrading please ensure you select the correct package in step 6 of the Upgrade Live Assist guide at https://support.liveassistfor365.com/hc/en-us/articles/360006210413#update365
Currently Power Platform Admin Centre (PPAC) is default selecting the Standard web package regardless of if you currently have Standard web package or the Web/USD combo package installed.
Always select the package you currently have installed and never select to upgrade both packages.
If you have any doubts which one to select contact firstname.lastname@example.org