Have you tried offering before he gets hungry? It may be that by the time he lets you know he's hungry he's already frustrated and agitated. It sounds like he eats better when he's calm, like when he just wakes up.
At any rate, I would just keep offering, whatever is going on is sure to change as soon as you get used to it and figure out how to work around it.
“We are not put on earth for ourselves, but are placed here for each other. If you are there always for others, then in time of need, someone will be there for you.”