For the same usage your bill this winter should be about double what it was last year, but would increase further if you were on a very cheap fix last winter, or have debt to pay off.
But you won't know what you bill will be until you've used the energy, so you must be talking about your direct debit, which isn't the same thing are there really people who still don't get this.
Have you checked whether the £550 is reasonable? What is your proposed annual energy cost (and no, it isn't necessarily £550 x 12) Have you looked at ways you can reduce your usage? Does the proposed DD amount take the £400 into account? Is there any debt on your account? At the moment, you should be slightly in credit so you don't get into debt over winter.
Look into things further to work out whether the £550 is the right amount and if not, you can ask your supplier to reduce it. If they won't and it's too much, you can go to the Ombudsman, but you first need to know how much you should be paying, which you might not be clear on at the moment.
BTW, it's not the energy companies making money. They're selling energy to us at a huge loss and are being propped up by the government. You need to be looking at Putin, the global markets and lack of investment in sustainable energy production and use to see who's causing bills to rise.