I've just got back from another visit to the Leigh Peregrines site where I saw at least three juvenile Peregrines and possibly four. Three of the juveniles have fledged and I saw them perched on the highest chimney being fed by an adult bird.
Once the adult had fed the two fledgelings on the chimney, it brought the rest of the food, a feral pigeon, to the nest box to feed the other two juveniles. Here's a picture I got on its final approach to the box.
I've had it confirmed that there are four young Peregrines as I thought because two male and two female chicks were rung on 13 May 2016.