Make a backup of your current game and create a shortcut to valheim.exe within the backed up folder, this backup won't break when the update will be released, that way you can start the game from the backup and keep playing with your mods until they are updated. remove the mods from the original installation folder or do a clean install so you can also play the "original" updated version as well.
And make a backup of your worlds and character(s) because i'm not sure if you can still use those with the current "old"version after they have been used with the upcoming H&H update.