Extra kit won't be an awful lot of use in the bus if you're half an hours walk away and having a hypo. Any extra kit you need to deal with pumping will be containable in a little enough kit to just keep with you, stick it in your backpack. Obviously if your doing DofE you'll be doing a fair bit of activity, so consider reducing basal or bolus, or just eating a few more carbs, uncovered. You might find snacks along the way don't need to be bolused for because of the exercise and you might be able to think about reducing meal time bolus too, depends how the exercise impact on blood sugars.