Just used several of my GGUs to book family for a trip to New Orleans. We’ve had trouble in the past finding U space on the SEA-MSY flights and this was just as difficult. They had incredibly flexible travel plans (anytime in the month of April), but it still took quite awhile to find a set of flights that would give them a trip longer than two full days, but less than 9 days and didn’t include overnighting in California. So - it’s possible to find space if you’re flexible, but would recommend snapping it up quickly when you find it