The ISP has to order the upgrade from BT Wholesale.
Most do it automatically for all customers that may benefit, (some users are better staying as they were), but it is done in blocks to a schedule over time. The more flexibility the particular ISP gives BT the cheaper it is for them. Moving individual lines, for instance if a customer gets pushy, costs more and that cost can be passed onto the customer.
The indispensable man or woman passes from the scene, and what happens next is more or less the same thing as was happening before.
My broadband basic info/help site - www.robertos.me.uk.
Domains, site and mail hosting - Tsohost
Connection - AAISP Home::1 80/20. Sync 57970/13958kbps @ 600m. - BQM