No, no set checklist. I'm certainly not the end-all be-all, but this is what I do:
1. Request RP account
2. (if possible/necessary) move your upgrade date to a more convenient date/time. E.g. not during month end close 🤣
3. Send out email/communication about release date to the wider business
4. About 2-3 weeks out divvy up the release notes between yourself and any other admins/highly NS-attached folks you can find to help (not to early, since they like to update the release notes several times while customer are actively going live 🙄 )
5. Meet back up and present your sections to each other, highlighting anything that is particularly relevant to your business or just really interesting in general.
6. Assign the UAT to the relevant business owners. I have list of UAT scenarios I've created already, usually a mix of:
a. critical business functions
b. ones inherited from previous admins
c. things that have gone wrong during previous releases or gone wrong in general
d. things from the new release notes (this is fairly rare TBH. unless you have a ton of custom scripting)
7. Make sure all the testing is complete prior to the release, and possibly send out another reminder email/communication to the wider business.
If you don't have a lot of custom scripting or bundles, the truth is, there's very little that's likely to go wrong. Of course you need to balance the risks for your business, so if there's something that's absolutely business critical you need to test that like crazy and if there's something that could wait a few days if it breaks, you may not need to test that at all.