Well...gave him the benefit of the doubt and he's sorted it now.
2 port valve fitted and wired in,
Tundish fitted to discharge pipe,
Discharge pipe routed to low level and caged off.
He's also sent pictures of him registering it via gas safe site.
Next doors cylinder is going to get the same treatment as it was fitted exactly the same as mine.
Have also advised him to read up on the regs and/or attend a refresher course considering I seemed to know more about them than him
Quite unbelievable that he didn't install the system properly in the first place.
You should get a certificate. Not a "picture of him registering it". What did he do, send you a selfie next to a postbox?