First of all please tell me if this does not belong in the support category.
When I was flying today I saw that some people were exceeding 350 knots using the same plane I was in (I was in an airbus 319 and they were in a 321, so sort of the same plane) and as I was at 21,000 feet going 345kts, they were at 30,000 feet going around 420kts. This may have been because they were at a higher altitude, or they were just exceeding the speed limit. If anyone could help me with this that would be great.
Also, I know this varies on the wind, pressure etc, but in general, what is the speed limit above 29,000 feet for an airbus A300 series? I fly at M .77 but I just want to confirm.