Icelanders also have what Finns have, a more or less reliable way of contacting the base - mages ind reaming. Finns are only capable of it within certain distance limits, Icelanders cover a larger space. So indeed, if that connection is lost it means the mage is out of the game and most likely the team is done for. Also true that about North Atlantic being kinda deadly for falling in. There's a damn good reason why, if there's a man over board situation, every singe ship that's nearby turns immediately towards the location. Even with a proper floating suit on a person lasts a few hours most.

YES PLEASE to the background story!!!