BOAC.
The answer is...........
4 Selected Transition Altitudes
4.1 The following Transition Altitudes apply to flights within or beneath the following Airspace:
† Note: Outside the notified hours of operation the Transition Altitude is 3000 ft.
ENR 1-7-2 (24 Nov 05) UK AIP
ENR 1.7 — ALTIMETER SETTING PROCEDURES
Aberdeen CTR/CTA 6000 ft
Belfast CTR/TMA 6000 ft
Birmingham CTR/CTA 4000 ft
Cardiff CTR/CTA 4000 ft
Durham Tees Valley CTR/CTA 6000 ft †
Edinburgh CTR/CTA 6000 ft
Glasgow CTR 6000 ft
Leeds Bradford CTR/CTA 5000 ft †
London TMA 6000 ft
Manchester TMA 5000 ft
Newcastle CTR/CTA 6000 ft
Nottingham East Midlands CTR/CTA 4000 ft
Scottish TMA 6000 ft
Solent CTA 4000 ft †
Sumburgh CTR/CTA 6000 ft †
I apologise for my pasting which didn't turn out quite as I thought!!!!!
Spiney