nicks:
My bill should have been generated yesterday but wasn't, although I have been given my new month's call and data allowance. I haven't had any new data charges added, but the earlier ones are still there. Never had a reply to my PM, but I wonder whether they are looking at it and have held back billing my account in the meantime.
Just an FYI - the bill is generated on the next working day after your bill cycle.
If no response as yet from your case with tech support - ask for a payment delay...