My son's appetite has been quite poor of late, and as a result he wakes up early every morning hungry. I want to introduce powdered cereal in his milk bottle to give him a more filling dinner meal. Can anyone recommend a powdered cereal for this?

I agree with Diana. I never liked nor agree with the idea of adding cereal into milk because 1) risk of choking increases and 2) cereal is food whereas milk is a liquid, I wouldn't want to encourage my child to have his meals via the bottle. Perhaps you could dream feed him at night so that he wouldn't wake up so early? Or it could be what Diana suggest and that he might just want to have some comfort and wants to play.