Originally Posted by
MSPeconomist
Does KEF follow the EC261 regulations? If so, OP would have a legal right to compensation in amounts prescribed by the rules. Otherwise, OP is asking for a refund of the fare difference for the downgraded segment and a customer service gesture.
That's a good catch, as indeed a flight from KEF-MSP would be covered. Still only gets OP up to 600 euros (about $705 USD.)