I'm having the same problems. I moved to plusnet phone in July, billing date for braodband is about the 10th of month but phone bill is later in the month. It would be much easier if they were both set to the same date.
I have the same problem and also want my phone and broadband bills to be in sync. I have complained bitterly but it's no use, nothing seems to be getting done about it. Orbrey told me the Development Team were having a meeting on Tuesday morning and he would let me know the outcome but I haven't heard from him. It's too confusing and I don't know what I'm paying for and it seems that Plusnet are in no hurry to do anything about it.
I have been with Onetel before Talktalk took over, as well as Orange and BT and I have never ever had problems like this. I suggested to Plusnet that they contact these companies for advice on how to handle their calls. If in fact they are a subsidiary of BT then they should already know. This problem has been going on for far too long now and needs to be resolved.
My next billing date is 12th November and I have been told the problem should correct itself as November is my third month. Well let's see what happens. Doesn't seem to have worked for other folks. If it's not fixed and there's no promise of a fix within a couple of days then I'm moving my phone, as it seems we are just being given excuses and just being told what we want to hear. Not good enough!!!