Skywork are an independent operator who picked up LCY-BRN after Darwen dropped it. It has been operated since summer or 2011, beautiful livery on the Dash 8 and Do328.
long the staple of the trunk routes from Scotland to Heathrow compared to a lesser number on board transiting at Heathrow, they are progressively moving from Heathrow to City
Indeed, remember GLA was dropped entirely, the raison d'etre for bringing it back was exactly that.