By this time BA had rebranded the 'Shuttle' as 'Super Shuttle' due to competition from British Midland who were offering 'Diamond Service' on board.
Interesting though that the InterCity Shuttle didn't actually compete with any of the airline routes. The shortest BA domestic route was still Manchester to Heathrow but with a full hot meal and bar service on a flight of under an hour! I think InterCity was still operating the Super Pullman sets on the Manchester to Euston route in the early 1990s though - 228 First Class and 376 Standard Class seats in 12 coach Mark 3 push-pull sets compared to 198 seats in a BA 757-200. There were three Southbound workings with these sets and one Northbound in the morning with the reverse in the evening.
IIRC, back then 1P02 (Birmingham Pullman) was also usually formed by the same sets.
so....back in 1993 with 86's and a DBSO British Rail Anglia, well.. British Rail 'Anglia/Gatwick Express', were doing Norwich to Liverpool Street in 96 mins, and now 26 years later a more modern fleet in 2019, they are sweating on doing it 90 !