Interesting if that is current as I’m pretty sure you can get 2 x 156 units (4 cars) on both platforms at Aspatria, and it’s been that way for many years.
That's the
operational length quoted in the 2022 Timetable Planning Rules, though it also states there's additional "unlined" length in both directions.
The Sectional Appendix, meanwhile, says
both platforms are 104 metres, which bears no relation to the sum of the lengths in the TPR!
Taking that into account, I'm going to go by Sectional Appendix lengths and say the new "winners" for London North Western are Bow Brickhill (Both), Aspley Guise (Down), Stewartby (Down) and Kempston Hardwick (Up) all with a length of 37 metres.