Going on the fares being charged, BHX-GIB must be selling very well which is no surprise seeing as it's a green list route and was previously served by Monarch who also did well on the route.
Can't find any return flights for less than £200 from BHX going all the way through to end of Sept.
I'm sure the route will also do very well from both airports, I have to admit I was sceptical when it was announced but the green list status for Gibraltar couldn't have given Eastern a better start!