Surferboy:
250 Knots at 10,000 feet.
Some aircraft have a good reason for being back at 250 Knots at 10,000 feet. For example, the BAe146 series of aircraft are limited to 250 Knots at 8,000 feet (and below).
This is an airframe limitation and it relates to the ability of the windscreens to absorb a bird strike below 8,000 feet.