My son listens to me and agrees to some schedule/plan. When he is in Yuck he doesn’t follow that. How can I handle that?
First of all, I want to commend you for recognizing that he’s not following it because he’s in Yuck!
So what you do in the moment is the same as what you always do when someone’s in Yuck in the moment — let them travel the curve. Let him get out his upset, and he will eventually stop and be able to re-access the “responsible, I have to do things even when I don’t feel like it” part of the brain. And if then when he realizes that his Yuck behavior hasn’t gotten him out of what he needs to do, he’ll do what he needs to do, especially if you’re consistent.
Your job is to not get sucked into the Yuck in the moment. Remember, you don’t need to do much… His behavior is simply his way of releasing his feelings of disappointment and frustration.
Remember too that you are working with him proactively on helping him find strategies that allow him to handle Yuck more maturely.