Adding 200mm asphalt to the runway is often done in 3 layers – 70mm / 70mm then topped with 60mm. But there are variants, depending on time available and the type of friction treatment.
After the asphalt is added, the runway structure will be a hybrid of concrete/asphalt. The behaviour of the pavement will be somewhere between flexible and rigid. Depending on the strength of the rest of the pavement structure beneath the concrete, it could be classified as either F or R. For common runway structures, it would possibly be classified as F, but that would be ultimately be the choice of the designer.
Resurfacing of asphalt runways is required every 7-20 years (the actual period of time depends on climate and pavement condition). The extent and design of the last resurfacing at Edinburgh are not known by me. If it was simply an overlay, often the pavement rating is not changed after such a resurfacing, so if it was changed then this could either reflect a (slight) increase in strength or perhaps the removal of a weak area during the resurfacing. If it was a ‘mill and fill’ approach rather than an overlay, then it was most likely the removal of a weak area led to a small increase in PCN. It could also have been increased because in the process of investigation/design, the designer realized that the PCN could be increased on the basis of the new data available to him. I have seen this recently at several other airports.
With or without starter strips, the runway length is such that this is still only a middle distance runway. Heathrow has genuine long distance runways: Runway Length 09L/27R: 3902m x 50m; Runway Length 09R/27L: 3658m x 45m. Gatwick has one: Runway Length 26L/08R: 3316m x 46m. Glasgow Prestwick Int'l just about has one: Runway Length 13/31: 2987m x 46m. But the existing Edinburgh runway is already extended close to its limit given the displaced thresholds at both ends.