SM, I do hope your session goes well today.
i am worried about how you are going to get through the summerhols - you can't spend 6 weeks under tis kind of pressure, cream carpet, need for constant tidiness etc.
I wonder if you can make an arangement with him: that you are responsible for looking after the kids during the day, while he is working / sleeping etc, but that you must be ablr to do it on your terms. You will get the house back to rights after they have gone to bed, but that badgering them all day will do your head in, put you in conflict with the kids, and could well put back DS1's progress!!! So that, yes, the house will be tidied up at the end of the day, but it is your business how tidy or 'homely' you have it during the day. Tell him it is essentailly your place of work during the hols, so it is your responsibility to manage it.
Fancy anyone planning a house with two small kids with a cream carpet! His priorities are way, way off. From where I am, it almost seems as if he istrying to design the children out of his life - or at least pretend they don't exist. It's really quite cruel.
tbh, if it was me, I'd find it less stressful to tell him to take his cream carpet and move out, rather than try to look after two kids for 6 weeks and not make a speck of mess.
You've probably left for your appt by now - but another thing to add to the list of things to talk with her about.
I wonder how your H will get on at the doctors????