Caz
Moreover, at para 32c the BOI stated " in the forecast conditions, the icing clearance would have allowed an IMC pull-up from low level flight to Safety Altitude over the Mull of Kintyre." Whilst the Forecast may have precluded a medium level transit over the Highlands, it did not preclude a temporary climb to Safety Altitude at the Mull.
I have to disagree, as the surface temperature was 9 deg C, allowing a climb to the 4 deg C level of about 2500ft. Local SALT was 2800ft.
The BOI also stated at para 16e "The weather was suitable for the flight but would have required flight in accordance with IFR in the vicinity of the Mull of Kintyre."
Have to disagree with that too. The flight was planned for VFR in VMC, all doable below the cloud, just off the coast. Why the aircraft did not turn left along the coast, but continued more or less straight into the Mull, will never be known.