Currently, trains from London King's Cross go to Glasgow Central if they are extended from Edinburgh but was it always thus?
Did they ever try using Queen Street instead? What's the story behind the extensions going to one over the other?
Thanks.
As others stated there were HSTs into Queen Street until around the time of the ECML electrification.
In 1988 there were two each way, to and from King's Cross plus one which formed an internal service only and then ran ECS. There was also a CrossCountry service, to Paignton, which ran from Queen Street, simply an extension of one which later ran only from Edinburgh.
The E&G had HST differentials specially installed for the HSTs in 1979, and from 1985 these were allowed to be used by the 47/7+Mk3 sets with the 47/7s then being permitted 100mph instead of the usual 95 for a 47.
Post-158 introduction the differentials were removed, in about 1992. It used to be possible for instance to go straight to 100 leaving Haymarket westbound, now it's 90 until around Edinburgh Park.