I would not be aiming to send cock birds on big youngsters and driving/laying again.
I think it is a big physical and mental drain on a pigeon.
I'd be aiming at sending them on 14 day to hatching eggs. If the babies are moving in the shell but they are not chipping, perfect.

If a cock has had races and sat and raised youngsters, he's done some work.
I'd be getting him on eggs and leaving him be, let him have his fly in the morning before he goes on the eggs. Rested up and keen for his eggs,
