Definition of a month

[#1]

My contract was for a fixed amount each month.  However I notice I am being billed that amount at 28 day intervals.  Can someone clarify what a Plusnet month is and whether I will pay 12 or 13 'monthly' payments this year.

[#2]

@Cjonesz We have an invoice date where we send the request to the bank and it depends on when the bank releases the funds as each bank is different. If your invoice date is 20th I would assume that the payment would come out on 25th or something.