Aberdeen's ILS's are Cat1 and look likely to remain that way.The ILS equipment supplied by Nats could work to Cat 3 standard,but the rest of the airfield(BAA's ) isn't up to standard.
It's surprising that they haven't tried to upgrade to Cat2,as it's a problem that always happens at this time of year.I guess that driving passengers up and down Scotland,instead of upgrading the Airfield is seen as ok to BAA(Ferrovial).