Strange Rear brake conversion on track frame, on a £1,300 quid bike good or bad?

I totally understand bodging a break to an old track bike if you have to, but not a brand new track frame form a shop.

Was it definitely a new shop14 frame? I thought they also sold Kierin frames - in which case, could it have been a shiny yet second-hand track frame...?

Also, were you trying to write "brake" or "beak"? :)