HD Air took over the BAC Express AOC in 2007. It operated the remnants of the Post Office 3.5 tonnes Skynet routes and a few private scheduled routes for a short while. The company founder (and driving force) was taken seriously ill and left the business. The contracts gradually ended and the staff dispersed. The company has had no aircraft or routes since about 2009. It is hardly surprising if the AOC has been revoked.