Weren't there a few exchanges in the north of Scotland a few years ago, maybe even now, where only BT Consumer and maybe one other could provide ADSLx? The restriction being because they had paid for the exchange enablement?
The three the poster lists that he can get are all BT Group (ISP) companies
My broadband basic info/help site -
www.robertos.me.uk. Domains,site and mail hosting -
Tsohost.
Connection -
Plusnet UnLim Fibre (FTTC). Sync ~ 53.4 (interleaved)/15.6Mbps @ 600m. - IPv4
BQM IPv6
BQM