The cabinet could be live by Nov 30th and it might stay live until end of May 2014 when your bt checker might change to accepting order.
There is no way to parse that sensibly.
Paraphrasing what you wrote, the cabinet might be live by the given date, and it might then stay live until the projected end date of the commercial roll-out, at which point presumably it self-destructs. Meanwhile, the date the cabinet turns live on the checker is entirely random.
I know BT are there to fool you and frustrated you.
Openreach are there to provide a service. Sometimes their best effort dates turn out to be unrealistic due to previously unknown problems, and they have to revise their dates. It sounds like wolvesmad's cabinet has slipped slightly. Openreach often put the public target date back a month on a small slippage, but this extra month is often worst case and the cabinet may well be enabled earlier than 30 November.
I don't think your cabinet isn't live until May 2014.
Removing the double negative, this says "I think your cabinet is live until May 2014". We'd better watch out for bombs or other destructive devices attached to the cabinet at the end of May, then, when Openreach are ready to blow up their expensive asset.
Much of the time you post inaccurate rubbish, which takes other people's time posting corrections. This time, you seem to have gone for posting surrealist rubbish.