Trouble downloading Big Sur RC2 - cannot install

I have been trying to update to Big Sur RC2 since 11/10 but I keep on getting the following error:
Installation of macOS could not continue.
Installation requires downloading important content. That content can't be downloaded at this time. Try again later.

This is on the "Install Big Sur" application. All of Apple systems are up.
Likewise.

When I try to do it manually from the installer, I am seeing

"(error code 112)/Volumes/Install macOS Big Sur/Install macOS Big Sur.app does not appear to be a valid OS installer application."

Likewise
Impossibly slow too. Working better with: https://github.com/munki/macadmin-scripts
Trouble downloading Big Sur RC2 - cannot install
 
 
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