I think they are confusing the white exhaust for steam
Here are the known times: -
1Z85 Ashford - Newcastle:
Ashford - 0623
Lenham - 0635/0637
Bearstead - 0646/0648
Maidstone East - 0653/0655
West Malling - 0704/0706
Otford - 0720/0722
Swanley - 0732
Bickley Jn - 0738
Beckenham Jn - 0743
Brixton - 0753
Factory Jn - 0756
Kensington O - 0808
Mitre Bridge Jn - 0813
Camden Rd E Jn - 0831
Kings X FT Jn - 0834
Finsbury Park - 0838
Potters Bar - 0845
Welwyn GC - 0851
Stevenage - 0856
Hitchin - 0901
Sandy - 0911
Huntingdon - 0923
Peterborough - 0939
Helpston Jn - 0948
Tallington - 0956
Stoke - 1009
Grantham - 1022
8 mins recovery time Stoke - Grantham.
Barkston Sth Jn - 1024
Newark NG - 1031
Retford - 1042
Doncaster - 1055
Shaftholme Jn - 1059
Temple Hirst Jn - 1105
Hambleton Nth Jn - 1111
Colton Jn - 1117
York - 1124/1128
Tollerton - 1140
Thirsk - 1152
Northallerton - 1202
Darlington - 1212
Tursdale Jn - 1223
Durham - 1229/1231
Birtley- 1241
Newcastle - 1246
5Z85 ECS Newcastle - Heaton:
Newcastle - 1255
Heaton - 1306 5Z86 ECS Heaton - Newcastle:
Heaton - 1713
Newcastle - 1724
1Z86 Newcastle - Ashford:
Newcastle - 1734
Birtley - 1739
Durham - 1748/1750
Tursdale Jn - 1757
Darlington - 1806
Northallerton - 1815
Thirsk - 1819
Tollerton - 1827
York - 1835/1838
Colton Jn - 1843
Hambleton Nth Jn - 1849
Temple Hirst Jn - 1852
Shaftholme Jn - 1900
Doncaster - 1904
Retford - 1915
Newark NG - 1926
Barkston Sth Jn - 1932
Grantham - 1935
Stoke - 1939
Tallington - 1948
Peterborough - 1955
Huntingdon - 2006
Sandy - 2016
Hitchin - 2025
Stevenage - 2027
Welwyn GC - 2033
Potters Bar - 2038
Finsbury Park- 2051
I Know the times end abruply at Finsbury Park
If there is any more updates I will post here during the week.
You will also notice there's none of this farting round at 75 mph on the ECML section
Bob