maggots in runner beans

[Two_Sheds]

I've never had this problem, but I googled "runner bean maggot" and found this: bean seed fly (Delia platura and Delia floriga is probably on its way to East Angular any time soon

Well I talked that up didn't I? On harvesting the last few dwarf Frenchies today for shelly beans, I noticed quite a few pods had holes in and gone rotten, and the seeds inside were rotting too.
On close inspection, I saw there were tiny little maggots inside the pod living in the rotting material. Yuk

I've popped them inside my butterfly tent to see what they turn into