I've searched and can't really find a hard and fast answer.  We are building a Westmarch style campaign, and I know the limit is 12 per campaign when content sharing.  My questions is what about if you don't turn on content sharing?  Is there any reason why the 12 user limit should still apply?  I want out players to pay Beyond for the materials they want to use, so it seems like it would be a win for them.  I'm just wanting to know if the limit applies even if you don't share content as the DM before I try to get 13 people to apply for it.

AFAIK A campaign has no actual limit (or it's really high). If the campaign has 13 or more players at anytime it stops being eligible for campaign sharing, but doesn't actually stop you having 13 or more players.

However, my memory is fuzzy on this and not in a position to actually test it.