I too have noted that many flights from BHX to DBX are blocked out over the next week.
I stand to be corrected (and no doubt will be), but today (8th) is the end of Ramadan and the start of Eid which is a big holiday for Muslims. Many people will be travelling home to be with their family to celebrate Eid and returning in about 1 week. It is more than likely that this is the cause of so many flights being blocked out over the next week.