A bit of a splash

Red Admirals and Tortoiseshells are adorning next door's buddleia along with a few dozen bees but it's far too windy to get a decent shot so this is a fartnarked Rudbeckia.

Does anyone know the easiest way to get my personalised number plate transferred onto my new car (yet to be built) without paying the DVLA twice?  I am part-exchanging it.