I don't have a rolling back strategy, just some general info:

- The latest update introduced a default-old branch that in the future should have the latest stable version before every update.

- Updates are tested on the Public Test Branch (PTB), so whenever you see an announcement for that, that's your indicator that a new update will soonish hit the main branch.

- Participating in the tests is entirely optional, but the more people help, the less buggy the update will be once it's pushed live.

- There is no reason to abandon your characters or worlds unless you use outdated mods. Modding is not officially supported yet, so you need your mod authors to update their mod. If you insist on modding Valheim, you should keep backups before and use a mod manager that alerts you to updates and allows you to start the vanilla game without deleting all mod data.

- If you have trouble finding your save data since the overhaul of the save system, check out the pinned FAQ in General Discussions or the pinned guide in the Bugs & Technical Issues sub-forum. If that info doesn't help recover your save files, please open a thread in the Bugs sub-forum with as much info about your situation as possible.