We saw 55007 'Pinza' working the down Hull Executive the previous evening, see....
https://www.ontheupfast.com/p/21936chg/29672776804/x55007-17-05-london-king-s-cross just south of Grantham. For some reason, BR did not diagram the Deltic that worked the down service to work the following morning's up Executive often preferring a Class 47 and to run the Class 55 back to London light engine. Pinza passes Essendine on the up fast no doubt heading for Finsbury Park. However, this it at odds with the website The Chronicles of Napier that has it already in London and preparing to lead the 08.31 Peterborough to King's Cross 'fast'.