Rickmansworth Canal Festival

With regard to there being two class 20 locos engaged with the Sarah Siddons trip, my sources have quoted that the Class 20's are to be used to move the new S Stock from Aylesbury down to Neasden and are required well in advance for Test Crew Training and route training purposes. Also it's been said that 20227, Sir John Betjeman, is slightly lacking in power so a chance to use 20189 as well was, perhaps chosen.