> At the moment it doesn't look like flight traffic will be affected.
Yes, in fact the opposite. Air traffic controllers in Iceland were planning a strike, and they've now postponed it because of the eruption, they claim.
I am in Iceland now. The ATC strike has been in the morning, delaying flights 4-5 hours but not cancelling them. Flights are still coming in and out today. Last night another guest at our hotel saw the eruption from the plane.