Link to topic:
SE's wonderful billing scheme - Final Fantasy XI Message Board for PC - GameFAQs
The above topic was posted by someone who reactivated his FFXI account on January 31st, and then got billed for the entire month of January as well as the entire month of February. When he complained about this on GameFAQs, everyone there started flaming him and calling him an idiot, saying that its was his own fault, even though it clearly wasn't.
Honestly, Square-Enix's billing plan is just fucking terrible, and anyone who tries to say otherwise or tries to defend SE in this regard is a moron and a fanboy. That so many FFXI players refuse to accept the fact that SE's billing policy is stupid is absolutely mind-boggling.