cgsecurity.org

Great, thanks for the quick response.

Used your alternative 2 seeing as I was half way there and started TestDisk fine.

I had already started Gparted > Data Rescue. That just has a status bar going backwards and forwards for the last 48hrs +, not sure whether it's actually progressing as status ...

I am following the instructions in TestDisk Documentation Release 7.1 on https://www.cgsecurity.org/testdisk.pdf

I followed this section:-
2.1.9 Ubuntu
As root on the Ubuntu system,
apt update
apt install testdisk

This appeared to run successfully with the last part showing
The following NEW ...