Re: Does ADSL always come from the exchange. Exchange only line.
The original question ‘does ADSL always come from the exchange ?’ , to all intents and purposes Yes, if your E/O line , and probably dozens of other lines, were in effect diverted through a newly installed PCP ( primary connection point or ‘Cab’) installed just outside the exchange , this was done to improve speeds , but obviously not every line now connected through this PCP are equal in length, so not every line benefits to the same extent. Some E/O lines are so close to the exchange that historically there wasn’t a ‘need’ to have those lines delivered through a PCP, and prior to VDSL , they probably had very good ADSL speeds due to the short line lengths, (close to 8Mb on upto 8Mb systems, and over 20Mb on ADSL2+) but ‘fibre to the cab’ obviously needs a ‘cab’ , so E/O lines are (were) disadvantaged as far as ‘superfast’ is concerned. Some E/O lines are very , very long lines, and those ( and I suspect the OP is one) ,and although no longer E/O , as it’s now routed through a cab, the line length means that VDSL would actually reduce speed rather than improve it ( there is a distance at which ADSL out performs VDSL) so no upgrade to VDSL is offered.
The OP’s ‘ADSL’ is delivered from the exchange , same as other ADSL customers, upgrading to VDSL requires the consumer to ask their ISP ( or the ISP to ask if the consumer wants it), it doesn’t just happen because a copper cabinet has a VDSL cab associated with it, if OR know the line is too far from the ‘cab’ to benefit from VDSL , they don’t make it available to ISP’s for that particular line. It seems to me that the OP is suggesting that they are connected to VDSL as they are now via a PCP that has VDSL access, but they are only being given ADSL type speeds from that VDSL cab, but that isn’t the case.
OR adhere to the ANFP ( access network frequency plan) which means that VDSL equipment cannot be co-located with ADSL equipment , that’s why they didn’t just put VDSL equipment in the exchange for E/O lines, but the had to build VDSL/Copper cabs , usually just outside the exchange building.