Start game fresh or not ?
No, as explained in the post by Jellyfoosh, you can copy your main save over. That said there is currently a bug with locked gateways. If you had a gateway unlocked (ie Drowned Lands > Quarry) it will be blocked again
Two save can be good to compare different situation/issue if something change, so you can transfer your save and also start from scratch.
What post?
A link to how we do that would be handy (both for myself and everyone else that end up in this thread), cheers!