I have been a Type 1 Diabetic for 40 years and also have a NCFE Level 3 Bushcraft Instructor's ticket, done in a flurry of enthusiasm which I maintain by teaching it and working freelance.
The key things are these: keep your blood glucose monitor with you at all times and, if it is sluggish or reluctant to operate in the cooler months/weather, keep it near to the warmth of your body. By and large, unless you are in the tropics or the desert, your insulin will be fine. The human DNA copies are generally more stable in a wider range of conditions but it is always worth being moderately but not slavishly watchful about it.
Always let the people who are with you know that you are diabetic. Take a little time to explain the symptoms of hypoglycaemia to them so that, if it does go wrong, they have a clearer idea about what is going on. Make sure that you also tell them where your biscuits, hypostop or glucolet/glucagon is so they can help.
If the circulation to your extremities is a problem, make sure that you keep your feet dry, if possible. Checking them before your curl up in your hammock or on the wood's floor is a few minutes well spent.
Eat regularly and test regularly. That is obvious for we Type 1s. I have found it really useful to 'run things a little high' when it comes to blood glucose levels: that gives both you and your companions some piece of mind. trying to keep things burbling along at between 5 and 7 mmol per litre is well-nigh impossible. Your Hba1c may look a bit odd afterwards but it will have been worth it! I have found, during prolonged times in the outdoors and, more relevantly, the woods, that I miss out my lunchtime dose of insulin because of the work and activity. My evening and nighttime test results thereafter were always spot on the money - never too high, never too low.
If you want any further information or advice, please p.m. me. I'm only too happy to help and I suppose that I do have a certain advantage in being able to talk from experience - nearly all of it positive!
Richard