I would assume that the new airfield at Riyan was built since there was no usable tarmac on the old one.
The "billiard table" was 01/19 by the way.
One of my colleagues from 105 Sqn days ferried a DC-4 through Khormaksar some years ago and took some photographs on his way through.
The old 84/105 Sqn HQ could hardly be seen for undergrowth. All the cladding had gone from the hangars and there was a row of dead MIGs sitting on their ars*s outside obviously having had there engines removed.