It seems to me that these free upgrade offers are badly worded , they are aimed at exchange based ADSL customers , offering an upgrade to FTTC ( fibre to the cabinet) , but the wording says something like you are on old copper based technology and the upgrade is to new fibre technology, but the truth is that FTTC is a hybrid system, it's still copper wires from the cabinet to your home.
There also seems to be a few cases of people who are already on FTTC being offered an upgrade , this presumably is just poor , or out of date records being used to advise customers.
It's not clear what exactly your problem is, if you think you are paying for FTTC but are still on ADSL, then an easy way to check is what speed are you getting ?, as the most you would get from ADSL around 20Mb ( and that would be if you very very close to the exchange) , if you are getting in excess of that , then you are FTTC and all they have done is made a mistake by offering you something you already have, it's possible that you could have low speeds but still be on FTTC if the cabinet is a long way from your home, again it's easy to check, just compare what you get with what is predicted here
If your home hub plugs into your phone socket, then you are not on a true fibre connection, its only fibre to the cabinet, and the rest is copper.
BT Retail, and other providers, advertise this as fibre, but its not.
A true fibre connection would have an optical fibre coming into you house, and a box on the wall similar to this one.
It should be advertised as higher speed broadband, only FTTP should be advertised as fibre.
I doubt the ASA know the difference.