Any idea why LH 419 IAD-FRA has been canceled two days in a row (15 and 16 Jan), leaving a 747-8 sitting at IAD for 2 days? We were there today and there was a gate that said that the plane would leave IAD at 1530 for FRA, there was indeed some activity around the plane that appeared to be preparation for departure, but then the flight was canceled again and the plane looks set to overnight for a second night. I figured it has to do with the weather and capacity restrictions at FRA, but perhaps there is also a mechanical issue?