Tommy Cook have flights from London and Manchester between 20 Dec and 6 Jan. Pegasus fly from Stansted via Istanbul into Dalaman. If not then Antalya.
My daughter is flying with Pegasus as she lives in London and even with the 90 minutes in Istanbul, the journey should be quicker than flying into Antalya as the transfer is so much longer (between 3-5 hours) Also if the weather is bad you have to go the long way round and if the flight arrives late then some people prefer to stay in Antalya to make the journey over the mountain in the light.