I have had a look at Venoms ticket history, and he agreed to pay the difference between the old account and the new. No mention of pro rata was made.
When an account is upgraded, no pro rata is charged. You are charged the full difference between your old account and the new.
The ticket history shows him agreeing to this, and then complimenting OpenWeb on its great service.
It is a pity that Venom is unhappy. We really thought we were doing a good job by upgrading him so swiftly and providing him with the upgraded speed since he agreed. However, when payment was deducted, which he agreed to, a problem is raised.
I see his point, but do not agree with the perceived intentions. We are not offering a free service. We need to make money to survive, therefore need to collect payment for accounts, upgrades etc.
In the future, we will spell out the difference amount, and the time window the debit will take place in.