If you are in a campaign currently managed by me and I allow you to switch, then you cannot go back to the other campaign.

You need to think through decisions you make. By that I mean, this campaign may last 1 week or it may last 100 weeks. Is it worth losing a spot in a campaign that has been long running for an extra 10$ for 1 week?

I'm not saying MintDice is a 1 week campaign, but it could be. It could be another longterm too.