What about connection flights? I’m supposed to go to turkey via LGW from Spain..
The general thoughts are that if you are a Transit Pax and stay airside there is no need to self isolate, of course when you get to Turkey you will have a temp test and have to fill in forms, what they do with you is anyones guess!
If you leave the airside and go groundside, that's where it becomes tricky, but I think most staff will be reasonable if the travel is out on the same day within a few hours. lets face it the damage is already done.