I was booking a flight and I selected Mint on the outbound leg, which was not much more than Even More Space, but on the return if I selected Even More Space I would get an error messages that "your departure and return fares aren't compatible." and it would force me to select Blue to return. Mint was not even available on the return flight. So JB is forcing me to spend less. Any idea why it would be set that way?

Tried different browsers and being logged in v. not logged in. Didn't matter.