Hi @jwurster & @jpentheroudakis,
First of all, my sincere apologies for this issue. I understand that Charitable has done a poor job of communicating the progress of the upgrade here, and it sounds like it may have been stuck in a loop in your case.
As I mentioned to @jpentheroudakis over email, you can close the browser tab or navigate away from the upgrade page if it looks like it is stuck in a loop. A new notice will appear asking you to complete an upgrade that was started earlier.
However, if there is an issue with the upgrade that is causing it to get stuck in a loop, I would love to make sure we fix that issue. If you could reach out to me via https://www.wpcharitable.com/support/ I would appreciate being able to get a better understanding of why this is not working as expected for you.
Cheers,
Eric