Unlimited broadband?

[#1]

I am a residential customer, on the Plusnet Extra Fibre package. I was surprised today to get an email telling me I was approaching my 120gb monthly limit, and setting out the extra charges if I exceeded. Admittedly, I don't pay much attention to the details of my internet contract, but had thought it was unlimited. Certainly, all the current packages advertised by Plusnet state that that is the case. So, wary of phoning, given the experience of numerous people on here, and failing to find a simple way of posting a question, I tried to get a response from the online chat. This invited me to post my question, which I did, told me there were two people ahead of me, and then that the chat service was not currently available.
As far as I can see from the packages mentioned on the site, I currently am paying more for a limited broadband than I would be for unlimited broadband from the same company. I'm not happy!

[#2]

Plusnet Extra Fibre was withdrawn on the 18th December 2012 and replaced with Unlimited products.  I'd ring the Customer Options team and discuss an upgrade with them...

[#3]

That product was last sold in August 2012
To change products and get a better deal as well call Customer Options (number in my sig) and select "I am thinking on leaving"
But before doing that note that the two current products are Unlimited Fibre - speeds 40/2 and Unlimited Fibre Extra - speeds 80/20 as you are on
If you put your phone number in http://www.dslchecker.bt.com/adsl/ADSLChecker.TelephoneNumberOutput if the lower speed for a clean line is less than 40Mb/s you will only have the option of 40/2

[#4]

Thanks for the replies. Very helpful.