A D-Cat still requires the 50 hrs IFR PinC plan time in order to teach IFR. D-Cats can only train people who have a licence (PPL+) so no ab-initio or CPL training, just ratings (IR/taildragger/type/multi). It's ideal for someone who only wants to teach IFR/multi as you can let your C/B expire as has already been discussed. They've (CAA) been talking about making the D-Cat a biennial flight test for some time. Haven't seen any NPRM's realated to it yet.