It has everything to do with which airfield, as (outside the London TMA) the airspace classification varies considerably between airports.
By way of an example, descending in the Scottish TMA below 6000 feet inbound to Edinburgh, you are in class E airspace until 10dme - that means 250kts or less; ATC have no authority to waive the 250kts rule.
Inbound to Glasgow, it's class D for most profiles, so ATC can let you do whatever speed you like.