Do a red or green day so you can have 2 each hex a and hex b , stick to free food all day before the meal, then you'll have 12 syns for cheese and 12 for bread, and as others have said, use flexi syns to cover any other excesses (eg like a glass or two of wine if you want it.)
Personally, I find green days easier if I need to stick to free food - could have JP & beans for lunch, something with rice, pasta or potatoes in the evening. Breakfast would be fruit and yogurt or scrambled eggs and grilled tomatoes. Hope you enjoy your meal.