FYI, I ran several parallel Springsteen and Jukes boards 10-15 years ago when we had technical problems with the usual ones or when the admins didn't want to run the forum anymore, it's not very complicated, really, it's mostly a question of having a lot of time on your hands.

There are 2 options:
1) you create a brand-new board where everybody have to register and start posting again from scratch
2) you create a brand-new board where you + nice & generous volunteers take the time to copy & paste the most important threads and messages so that the most interesting conversations don't disappear.

Some friends of mine did that a couple of years ago and it took us only a couple of months to select and import the most interesting threads into the new board. Of course it was a lot easier since we were not bothered with 4 pop-ups each time we clicked on a page...