My billing month runs from the 9th of a month to the 8th of a month. My initial contract was £3.99 p.m. My new contract is £6 p.m. I made the change on the 9th September i.e. right at the start of the contract period. I have been charged £7.86 for the month. I cannot see where pro rata arises as I changed on the first day of the period. Any ideas?Thanks