Customer beware here. It's just caught me out.
I was very confused when I was billed for a months usage which I had no way of using, turns out my contract had a 30 days 'notice period' in it.
So Orcon got another months bill out of me for absolutely nothing, which in my opinion is quite scummy behaviour, I thought I was being clever cancelling right before my billing date.
Just let this be a warning to anyone else that if you're thinking of changing ISP's to tell your ISP and then set the physical changeover date for a month later.
Yes, buyer beware etc etc but hopefully this forum post can help save others the same mistake I made.