I think the OP (post 27) is now getting the 14:34 Eurostar service, so he will have more time to get down to London (including on the direct sleeper from Pitlochry).
Yes that true.
My journey now is (bought tickets so no chance to change it):
London 14.34 - Bruxeless 17.33
Bruxeless 18.25 - Koln 20.15
Koln 22.28 - Warsaw 10.05 (this train is always delayed so that'll be some time after)
Now I need only to find some cheap tickets from Pitlochry or Edinburgh to London and thats it.
Thanks all of you for advice one more time.