Flown there for four years. This is the way it is.Whether it is caused by weather or by "military activity", there is nothing you can do .I always tried at least not to have the pax's on board , otherwise the script was always the same: after one + hour paxs gets enough , wants to go home ...always 10 minutes away from your slot.
During flight you were lucky with the speeds change. I have got holdings during climb out of departure airport , while still more than 3 hours away from your destination. Eventually got pulled out off the airway to a 40 minutes holding pattern due to "flow control" at your destination.
But I must admit it was very interesting flying in there. I do not regret at all.
Enjoy your "flow controls" . Buy an Ipad and load it with plenty of movies to get prepared for the summer. Flow controls due to really bad weather tend to be quite long. You might be able to watch one or two full movies before you can get airborne, pause from time to time to make a PA to the paxs...
Cheers....