The 250kts speed limit does not apply to the following:
Flights in Class A and B airspace
IFR flights in Class C airspace (No Class C in UK)
Flights in Class C and D airspace when authorised by an ATC unit
Test flights in accordance with specified conditions
Aircraft taking part in flying displays when authorised by the CAA
Aircraft subject to written permission granted by the CAA
Aircraft not subject to the ANO
*Note for all you guys and girls flying in to EGPF and EGPH, when you are transferred by Scottish to approach, you will (90% of the time) transit through Class E airspace where we as controllers cannot lift the speed restriction, we may well say there is no ATC speed restriction, however this DOES NOT override the 250 below 100 it just means that we don't have a specific speed for you to fly at