Crikey, Chris, how much sweet stuff have you got in the house? If you’ve got a lot, I’m not sure eating all of it in one day is a good idea. If you really can’t bear to chuck it out, why not have a few days lead in to the diet, gradually reducing the amount of sugary stuff and carbs to a point where you have none left in the house and you are ready to cut the calories? Your body will be struggling if you put loads of sugar in it all in one go.
Best of luck with the diet in any case. You’d be surprised how quickly you can lose the sugar craving.