Cereal is one of the danger foods, along with bread, spuds, rice, pasta, anything made with flour, and most fruit. We also need to be careful with milk.
Breakfasts can be difficult, I know. It doesn't have to be traditional breakfast food. It could be any mixture of cold meats, eggs cooked any which way, cheese, a full fat unsweetened yogurt with a few raspberries or strawberries. It takes no time to make an omelette with 2 or 3 eggs, and perhaps add some mushrooms, bacon bits, cheese, tomato, whatever floats your boat. It could even be left overs from a previous meal, heated up. As I mentioned, it means thinking outside the box. In fact, if you go to a cafe at lunch time you could have a fry up there (without bread and beans), or an omelette. MacDonalds will serve burgers without the bun and chips and give you extra salad.
I see you are on insulin - so you do need to be careful if you reduce your carbs. What you don't need when on the road is a hypo so be very careful and test, test, test.