Jic, congratulations. And thanks for posting this thread.
I'm waiting to hear on my dream job. Not got it yet but if I do, I plan to spend a week before it starts getting super-organised.
A day decluttering the house of tat and outgrown clothes etc.
A day deep cleaning the house, so if a cleaner comes to look round she doesn't run screaming from the scene.
A day sorting out food - cleaning fridge and freezer, bulk cooking stuff like spag bol sauce, making an online shopping list for the basics so the weekly shop doesn't take forever. And buying ready meals in bulk for the early days when I'm too knackered to cook.
A day getting organised for work - stock up on work clothes, buy season ticket etc.
A day on laundry - everything washed, ironed and put away, beds changed etc.
A day focused on kids' needs. Take them for hair cut, dentist, new shoes, check all their clubs and homework days are marked on the calendar, not just in my head etc. Library books handed back, homework and clubs subs up to date etc.
Also plan to ask a handful of good friends and neighbours, if something goes pear shaped - the kids are ill, for example, would they be prepared to step in to take care of them at short notice, and I'd offer to pay them going rate. That way, the kids are being looked after by someone they know and like if they can't make it into school or nursery.
I'm hoping having a head start will make things easier.