Op, I know you e explained about the TV etc, but you are assuming any change would tie you into a new contract which might not be the case. You need to phone them up and ask them what you can do because you can't afford it anymore. If you don't ask you won't know.
I totally understand why you don't want to rock the boat with the older DC, but how long have they been paying that amount for? Rather than outright increase, is there a way of reducing what you pay for, for them.
For example, IMHO, the Netflix should go. Who uses it most? If the older DC could they start paying for it?
WRT meal plans, your're right to plan. Are you also buying snacks, treats, soft drinks and so on? I find that sort of thing is disproportionality expensive, especially individually packaged snacks.
And finally, have you done all you can in terms of heating reduction, insulation, length & temperature of showers etc.
Please don't put the phones on a credit card. Getting that laid off in December will be a huge milestone.