For an official HeB 28g of porridge should be eaten along with 1 ryvita. If you don't have the ryvita then really you should syn the porridge which is 5 syns for 28g.
So if you didn't have a ryviata, swap your HeB's around. That would save you 1.5 syns on your sw. Also like someone else said choose different crisps. French fries are only 4 I think and Square crisps are 5.5, ryvita limbos are 3. I like quavers which are 4.5.
Or go for something different for lunch. Try a tin of Branstons ravioli...1 syn. Or a mug shot which are free. Then you could have a bag of low syn crisps or a kit kat or something. Or maybe make yourself some cous cous cake with lemon curd...0.5 syn per slice and very tasty.
If you're interested in quiche recipes there's one that I make using cous cous as a base instead of pastry. It's great and you can't really tell the difference. I use Ainsley Harriots flavoured packets, make it as directed then grease a flan dish with fry light nd using the back of a spoon, press the cous cous into the dish. Like you would with crumbed biscuits for a cheesecake. Bake it in the oven for 10-15 mins and then you can put whatever you like in as a filling. I use 56g of cheese (2 x HeA) and bacon, onions, peppers, mushrooms, sweetcorn....whatever is lingering in my fridge. Mix it with 3 eggs and a couple of table sppons of LF fromage frais and bake for about 20 mins until cheese has browned. It tastes just lik a 'normal' quiche and if you cut it in half the only syns on a EE day is 6 for the cheese or a HeA. I split mine over 2 days and use my He for them. I have it with a J/pot and beans or chips with beans or some coleslaw....it's great and doesn't feel like a diet at all. Last week I had a 1/4 of quiche (3 syns) some loose meat such as chicken or ham (fat removed), J/pot, loose sweetcorn and you add some salad etc or coleslaw.
Mix it up a bit and stop your food and diet from getting tired. Also look in your book and see how many speed (S) and super speed (SS) foods you like......Chicken, tuna, baked beans, Petit pois, apples, carrots, cabbage, Strawberries, onions, tomatoes...all these foods will help speed up your losses so eat as many foods with S or SS next to them as you can.