(02 Nov 2013, 6:26 pm)Dan wrote Do you mean 4840 (340 GUP)? If so, I believe it's just a private registration plate. I'm sure Arriva have a few of their pre-2001 registration plate buses with private registrations too.
CRZ7495 ended up with Preston Bus - see photo here.
I don't believe ERZ2028 has been sold to an operator as of yet.
That most probably is a private plate, N.I plates is always 3 letters, 4 numbers, i.e. ABC 1234