If they are stuck in Iceland over the night, then Icelandair has to offer them hotel rooms, food and two phone calls, and in some cases also 600 euros per person. This is a legal requirement due to an EU regulation. Due to Iceland's European Economic Area (EEA) membership, the regulation also applies to Iceland. There is a good introduction to the EU regulation in this thread on the BA forum (read the first seven posts): https://www.flyertalk.com/forum/brit...61-2004-a.html