Enough in the early stages of the route for QR to confidently announce a daily service.?
That's flying a third of the seats empty, so I would say not ideally, but they likely will. With Etihad dropping in next summer that's going to be a challenge to fill all those seats even with the obvious advantages these guys have on costs.
Emirates came to GLA and basically made going East so much easier, it would appear QR have not taken as many BA / KL frequent fliers as they were expecting from the EDI catchment area or worse, they were taken by EK from GLA and are staying loyal for the most part for Skywards points.
Also worth noting with QR is that they went straight in with the B787 rather than the A332 so expectations would appear to have been high(er).