They actually did this before, where they shifted list prices and the old items were allowed to stay but not be relisted.

You do bring up a good point though:

Any items currently listed for rent would stay listed, until expired - then would have to be relisted, following the updated rules (should this move to the next step).

But let me ask you this: if you were renting a card out for .3 DEC and it was rented 10/60 days... you would make 3 DEC - 1 DEC for listing fee... so that is 2 DEC Profit...

Wouldn't you rather rent a card out for 3/60 Days and make the same profit?

I would.