ADF
I assume that what the CAA intends is to remove the REQUIREMENT to have ADF while flying IFR in controlled airspace, and at this time no suggestion that NDB's will become unavailable (although I am pretty sure that eventually that will happen too).
By the way, the ADF is the thingy you have in the aircraft while the NDB is the thingy on the ground that transmits a radio signal: they are not the same thing.
With modern GPS systems and PDF's one can now have a bearing indciator pointing to wherever you want which looks to all intents just like an ADF RMI. The only difference from a true ADF is that it is not actually in receipt of the radio signal ( together with all its well known errors) and there is no dip error. This makes a vastly superior, simpler to use, and more precise effective ADF than a true ADF. It does seem to me that one should be allowed to substitute this for an ADF in order to perform an NDB approach where at present there are no official GPS approaches. In due course I would expect in any case NDB approaches to disappear and be replaced entirely by GPS approaches.