Istanbul?
I am sure Bristol management would or maybe already have contacted Turkish Airlines considering it is an airline similar to Emirates when it comes to ambitious plans.
Their UK expansion somewhat stalled after the BHX route started but this did commence at an unfortunate time in terms of the economy. However they have stuck with it and loads have spectacularly improved (no idea of yields).
Now Manchester, Birmingham and Gatwick are to see increases and Edinburgh is an intended new route. Turkish also don't seem to worry too much about how close other airports are and are more intent on feeding their two main banks at Istanbul Ataturk.
Their financials have dipped somewhat recently no doubt partly due to the expansion but I wouldn't be surprised to see a Bristol route in future.
Pete