A couple of months after mid summers day they are getting into the moult, and here's an interesting thing.
There's about 40 out there. They get a carefully researched measure called the "Pineapple tin" full of feed in the morning and at night. It has been ample, I have been throwing the scraps out to the wild birds. Now I find them falling on the feed like they are starving.

Back in Bendigo they all flew out every day and had plenty of food. I never noticed any change due to them moulting. Here they are on a set amount and it shows, they need more feed. The moult obviously puts a load on them.
Mine are getting a good mixture for pigeons which are locked up. Not too much maize or peas. They get their veggies and garlic and cider vinegar, and some fish oil a couple of times a week, and their grit replaced daily.
I don't believe there is any such thing as a "Moulting mixture". Pigeons moult perfectly well on any decent feed. What I have discovered, belatedly, is that it places demands on them and they need plenty.