Non- transferable Registration numbers

[Charles P]

If a non transferable number was issued to a vehicle, does anyone know whether it can be replaced with a cherished plate or preferably if obtainable, the vehicles original number., or does non-
transferable mean that it is perminent ?

Yes. You can replace a non transferable number (such as age related) with a plate bought on the open market, subject to the usual rules about not making the vehicle look younger.
The discarded "non-transferable" plate goes back to DVLA.
I know of a car where this was done after the owner of the old car with an age related number bought the original plate back from the owner of the much more modern "host".

c