No thats my point my original licecnce is a PPL(A) SLMG not SEP.
CAP 804 simply refers to the conversion of a PPL (A) and does not specifically mention PPL (SLMG). If you go for the EASA PPL with TMG rating, then it will be very simple to add a SEP Class to it, you cannot do that with either a SPL with TMG or LAPL(S) with TMG. Ultimately, you will need two licences to fly SEP and sailplanes but, go for the deal that gives you the most.