Hi Crazy, I am one of the voices at Scottish Information. It is always nice to hear complimentary remarks about our service. I believe London Information have a transmitter on the top of Snaefell on the Isle of Man so coverage in that area should be pretty good. As for Scottish on 119.875 we have a transmitter on Lowther hill to the east of Dumfries so also coverage pretty good in that area. We always liase with London regarding traffic heading into their airspace and visa versa London do the same with us if they are not too busy.
As for the FIR boundary, that is 55N but the AOR "Area of Responsibility" is further south than that and Scottish Info are responsible for traffic north of a line Carlise-IOM approx.