I’m due to go away for 8 days skiing in jan, should I reconsider at this early stage? How do T1 manage all day activities like boarding/skiing,
Give the ski-ing a go, man, but learn a bit about the biology first. You've probably got a heads up on this from your kids experience but it's worth restating.
You eat carbs, they turn into glucose, it goes into your bloodstream, gets fed out from small capillaries into interstitial fluid between cells, then it goes into cells to be used as energy. Insulin works as a chemical gateway to allow that last step to happen - not enough insulin, glucose won't get into the cells and will just stack up.
But the thing to notice here in a ski-ing context is that there's another thing happening. There's other stuff going here - when you're exercising. Cells have stuff called Glut4 responders. Glut4 will let glucose into cells without insulin when you're exercising, which is what ski-ing is.
Your dsn might be telling you to use x units for that meal, but if he/she doesn't know you're going to be racking up some time on the slopes, that'll not work out too well.
You'll end up with a double whammy - insulin and glut4 both working to reduce bg.
That doesn't mean you shouldn't ski, far from it. It just means you should talk to your dsn about seriously tailing back your bolus shot for ski-ing days. And making sure you've got a backpack with lots of lucozade in it.
I'm not trying to discourage you from ski-ing (I've spent years post-T1 dx hacking around Scottish ski slopes - boilerplate ice: we're the guys to call!) but do be aware of how much glut4 response can affect things. It's not a bad thing. It usually just means you can substantially rake back your normal bolus dose.