In reply to a post by Pheasant:

Maybe it would be easier / cheaper to actually keep PDPL in perpetuity....

People move house. When they cease their PDPL line the next occupier won't be able to take it - it's not available for new provides or working line takeovers (*). Naturally over time the number of lines will tend towards zero.

After a decade or so, the last few holdouts will likely be offered something else. During that time, the Shared Rural Network should have reduced the number of mobile not-spots, so it will likely be a terrestrial mobile service for most, and satellite for anyone else.

For the OP: do nothing. Stay on the analogue PSTN service you are on, keep paying for it, and you should be moved to the continuation service transparently when PSTN is switched off.

(*) Possibly if people raise loud enough complaints under the USO, and/or get their MP involved, there might be some exceptions granted.

It was a slightly tongue in cheek comment, but they will have a job to decide how to viably continue service to some of the technically more challenging edge cases like this once PSTN goes and they retire PDPL in March 2031