Traditionally, when a lord/duke formed a new religion, they gave up their landed nobility titles.
With the new system, what happens? Would a duke lose both a lordship and his dukeship? Would he lose his lordship but keep his dukeship?
I was thinking about this the other day and couldn't find anything that said it either way, so was curious as to how it was taken into account.
Probably is/should be on the "to code" list.
