Thanks DrYak,
That advice makes it seem achievable. No time to try for a few days, but it will be very helpful, so thanks very much.

A more general question:
Considering that all was working well on sailfish X and no system changes were made, is flashing android just a way of satisfying the repairer that the problem is indeed a hardware fault? Or is there a genuine chance it could be a sailfish problem, in which case, should I just reflash Sailfish X as I have the instructions and images ready to go?

Thanks again everyone,
Justin.