Sue,
I had a friend stay in our villa Last 2 weeks and they returned on Friday as normal, they were aware of them going into administration but said it did not change anything. The flights were ATOL protected so in this case the CAA step in and take over with regard flights, they will have details of those that are in Turkey, as they will have had all the information passed to them from the tour operator H4U. This only applies to those with return flights as it is an obligation as only one part of journey has been made. Unfortunately in your case you made 2 separate bookings so the first one has been fulfilled but the second has not started yet. It is ATOL protected but it is the same as those that have future bookings cancelled.
We were going book seperate flights last year but after goldtrail going decided best to have flights with same airline.
Hope you manage to sort something out.
David