Thanks for the info fxh and lennier.
Sounds like they are bespoke tailors from what lennier is describing. The 'part-way' done suit is probably the basted fitting. It is standard operating procedure for tailors. In that case, it makes sense that it would cost more than PJohnson who modify a standard pattern, offshore.
I might go to them when my piggy bank fills up. Hopefully they will work with customer supplied cloth as I have an awesome length of suiting which I want to get made up.
They certainly were proper old school bespoke years ago when I used them.
I doubt it would make sense for them to send offshore if they can do in house. But I could be wrong.
Best way is to ask them - they were always friendly in the past.