How much notice do I have to give

Question

I am a BT Total Broadband anywhere option 3 customer with 2 mobiles (very expensive) and regrettably after 32 years with BT it is time to go elsewhere.
I think according to the terms & conditions here -
http://www.productsandservices.bt.com/consumerProducts/dynamicmodules/pagecontentfooter/pageContentF... 
If I am moving to a new supplier (not cancelling) through an approved process (presumably MAC & PAC codes) I only have to give 14 days notice see below.......
Ending the service
Once we have provided the service, you may tell us to stop providing it at any time by giving us 30 days' notice. We will accept notice via a range of methods including phone, e-mail, online chat and in writing. You can contact us to give notice using any of the contact details set out on your last BT bill or any other means of contact we have given you, for that purpose. If you are switching to another provider through an approved process, the notice you must give us will be 14 days. We can stop providing the service to you by giving you 28 days' written notice.
However when I try and get an authoritative answer from a human being I get told it's 30 days. Now my prospective new provider(s) will migrate me in about 10 days, which if the humans are correct, would mean me paying twice for my telecommunication services for 20 days, which does not make any sense at all.
Now I've had a few problems with BT over the last couple of weeks (which is what has prompted me to look elsewhere) and every time I have spoken to someone I have had a different answer to the same question (on different matters). Essentially it is all so complicated, that not even BT's own people know what they are talking about LOL and I have completely lost confidence in them being able to give me the right answer.
So does any one out there know for certain how much notice I am required to give?

Answer 1

Well I'm glad you think it's clear because it isn't clear to Customer Options (quote 30 Days) or Billing (quote 30 Days), neither of whom if they are wrong, have any idea of what BT's terms and conditions are. In fact, customer options thanked me for pointing out to them the 14 days bit which he said he wasn't aware of!!!!!!
It also says -  "We will accept notice via a range of methods including phone, e-mail, online chat and in writing."  but when I asked about giving notice (before I read that bit) guess what? I was told I could not give notice, they would not accept it from me, they would only accept it from the new service provider.
Similar problem last week. I was on holiday in the UK and it looked like I might bust my mobile data limit, so I ring customer options, checked where I was, they can tell you how much you've used up to a couple of hours ago, as the online usage is always 2 days behind, "yes I can add another Gb of data for £10.20 or its £1.50 per Mb if I go over". Wasn't looking too bad on Monday but by Wednesday.......... Please can I add that extra Gb of Data we talked about on Monday? "Errr, no you can't add any extra data but don't worry, its not £1.50 Mb it's only 20p". LOL that's still a lot of money, so I stopped using the phone as a wifi hotspot, which was not exactly convenient.
So as you can see, the people in customer care don't actually know what they are talking about, which is a bit worrying.
BTW The wifi hotspot worked really well ............. on the edge of Exmoor ......... Live streaming TV of Le Mans 24hrs over the weekend. Which is how I nearly bust my data limit LOL.