European officials expect commercial flights to return to nearly 100% by today. But carriers note it will take several days to clear the backlog of passengers stranded by volcanic ash from Iceland. Ash from the Eyjafjallajokull volcano forced airlines to cancel thousands of flights, and a return to normal travel patterns might take several days, experts say. Meanwhile, observers say the crisis has highlighted the value of traditional travel agents. Many agents have worked long hours during the past week, rebooking and finding alternative accommodations for stranded passengers.