If you are on some form of FTTC, that land-line actually had to be lengthened by twice the distance from the existing PCP (Phone distribution cabinet), to the new FTTC Cabinet, ie the new link cables between the two.
If you have any form of alarm system working through the land-line before upgrading to FTTC, the full length of that land-line, including the two new links, is required for that alarm system to continue to function.
Subject to anyone else having better, up-to-date knowledge, it was also required for Emergency Calls.
Note the advice to use a land-line, automatically giving a definite location, compared to the uncertainties with mobiles.
Edited by eckiedoo (Wed 27-Apr-16 18:16:12)