aww hun, any change to a child's day is going to effect them and seems tyler is perhaps effected by daddy not being around.
to be honest, i know its hard but i wouldnt change his days at nursery,because he will be getting use to it soon, it always takes a few weeks for a new routine to be settled.
rich gets clingy everytime he goes back to school after a holiday, especially if i'm not looking well, no matter how much you hide it, they know.
plus you changing your hours, might sound good but a full day can be very tiring and then having lo on your days off, is not really resting. whereas your body is use to you working these hours.
really not sure if i;ve helped there, but just give him a bit more time and see if he settles a bit more, he will eat when he is hungry and maybe mention to the nursery that you worried abotu his eating and you want them to record everything for a week, nurseries tend to give alot of snacks through the day as well as main meals, so maybe he just eating a bit too much during the day
hope things get better hun xx