Finally able to close this one: https://github.com/nul800sebastiaan/Cultiv.Hangfire/issues/37

And now I'm updating the site that was stuck on v13 to v15.. 🚀 Upgrade was about 5 minutes of work, but I'm getting some unexpected null ref errors now, so something fell over, probably during the .NET version upgrade. However, the backoffice works and it's just my custom code that's needs a bit of work.

Actually, I checked the backup of the project and the code had been broken all along 😅 It worked just fine, had to replace a Nested Content with a block list. That was annoying, I did lose the content even though I tried several options to migrate. I am not sure why the content never survived, but it was only 6 items, so I just copy-pasted them instead. Cloud site is now running v15 on live, it was a simple push up to Cloud as usual and as if by magic, it went from 13 to 15. I'm a happy customer!