The situation is not as it may seem!!
The neighbouring property, decided that they would renovate and extend their bathroom by claiming the width of the wall and the cavity to install their vanity unit and shaving cabinet.
Unfortunately the property I was working in decided to renovate their bathroom.
Between the brick walls is where the services are located. I removed some bricks to gain access to the cavity to re-run hot and cold water.
Alas, there was no cavity, due to the neighbours aquisition of it.
I unfortunately ruined their recessed vanity unit, recessed shaving cabinet and their recessed mirror, amongst other things.
Beautiful situation..I will keep you informed as to the outcome.