I assume that you are referring to ex-military types that are operated under CAP632 (e.g. Jet Provost).
Yes I'm looking at ex RAF jets.
Would this be strictly VFR flying
Yes
These are all Annex II aircraft that are flown under national regulations and require a UK licence and not a Part.FCL one (because EASA does not recognise the types and therefore does not issue a type rating). An Aircraft Type Rating Exemption (ATRE) is then required for each type.
How does this work do I have to do my licence twice? the annex 2 thing really confuses me.