The answer to that is simple in that previously BT is now supposed to be totally different with regard to line speed, reliabity and performance.
To answer that you need to consider why I went elsewhere and that was down to poor performance tied, (to unjustified constant price increases).
The previous poor performance was mostly down to the inadequacies in the Openreach System and the automatic DLM System. (ie. On an 80/20 FTTC BT line the speed declined to under 28 mbps and as it declined, (according to BT at the time), it was always the target speed for the line. - When we moved to Zen the same FTTP line had a steady 54 mbps after Zen controlled the Openreach Engineer visit and a very good Openreach Engineer we had a very low SNR Margine.
These days many of us eventually have FTTP in the UK and recently Zen has not been as reliable as it once was. - Most others ISPs. (including Zen), use the BTW backhaul via Openreach. - Anacdotally, BT are now really good with regard to speed, service reliability, low latency and performance and that is why I am returning to BT.
I already know that the BT Customer Service is much better than it once was because I have spoken with them so that is a good sign.
Yes; I know that regular unjustified price increases are still part of the BT business model but since line performance is key to us we can live with higher prices if higher levels of performance apply but we will soon find out if BT are now better.
