Great trip up to Castle Kennedy from Blackpool thank you fishbangwallop - technically still inside the London FIR but always tune into you when I can
Not quite right with regards to the airspace. Although most charts show the border between London and Scottish airspace as 55N the actual "Area of Responsibility" differs greatly. Roughly the southern extremity of Scottish Information sector is along a line Newcastle just south of the DCS VOR then down to south of the Isle of Man then west to the Irish coast. If you take a look at the legend on the 1:500,000 aeronautical chart it gives a small diagram showing the airspace and frequencies to be used. Also check out the following page in the UK AIP.
http://www.ead.eurocontrol.int/eadba...2012-09-20.pdf