Regarding the 139, I will go on record that it seems to be a fine machine, frankly. The teething problems it has seem monor and easily fixed. It also gives the customers a full choice, with its bold design that eliminates the HV curve at offshore conditions.
The S76D is squarely in he 139's face, for sure. I will bet the guys at Sikorsky have already asked the customers with the checkbooks what they want, and are building same. Fears of not meeting "OGP" rules are foolish, the oil companies are consulted for the design requirements whenever an investment is even considered. I believe that the S76D shares the same fuselage with the A thru C, but there is a window redesign.
The choice customers face is payload and range vs single engine immunity. The short range and high fuel burn of the 139 is dictated by its enormous engines and the weight of its drivetrain, all of which are optimized for engine failure. As I hear it, the 139 is not burning any barns in its sales, perhaps the folks who get paid to carry stuff don't want to pay to fly the drive train of a 21000 lb helo while only carrying the payload of a 12,000 lb one.
Let the customers decide!