I’m glad to hear that this solution has been helping people.
In the meantime, we have another improvement to the script, so if you still have problems with not being able to update after running the version of the script in Endless OS 3.2, please try downloading the very latest version of the script from GitHub until it is released as part of Endless OS 3.3 (sometime in October):
rm -f eos-fix-ostree-repo
wget https://raw.githubusercontent.com/endlessm/eos-meta/master/eos-tech-support/eos-fix-ostree-repo
chmod +x eos-fix-ostree-repo
sudo ./eos-fix-ostree-repo
Please be patient. It may take several minutes (without any status updates) for the command to complete. Wait until the command line prompt returns, and then proceed with OS and app updates as normal.
(Note that the rm command run first is just in case you had previously downloaded an older version.)