For the Wow operation we used BIEG BIAR for all narrow body types and for the A320 BIRK subject to a clean runway. Due to the large distances involved in diverting to the first two airfields it was worth sitting in the overhead at KEF waiting for the snow shower to pass and then have the runway swept. The airport at KEF were very efficient in snow cleaning
The diversions also have a number of issues including challenging approaches and small aprons.When the Iceland alternates were looking poor we would look at Scotland but this could mean a tech stop in Canada or the USA to load the required fuel.