apt update gives error on fresh PVE 5.3-5 install

[HenryTheTech]

I modified /etc/apt/sources.list as outlined here.

Still, I end up with this nuisance message:

Reading package lists... Done
E: The repository 'https://enterprise.proxmox.com/debian/pve stretch Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.

 

[HenryTheTech]

*edit - for whatever reason this message just stopped on its own, after adding GPG keys for another unrelated source.