(08 Jun 2016, 8:44 pm)L469 YVK wrote You never know.
Although with a bit of a struggle and given the Northumberland contracts that have often seen 6116 / 6117 in use on an almost daily basis as well as the abandoned GKN mods to 6104, the Clippers have coped reasonably fine with 1x spare.
Got to remember that the 56 has been timetabled with slightly more running time plus increased layover at Park Lane meaning that unless a B9 breaks down or is in for a PSV, then the likelyhood of needing a spare decker is reduced somewhat.
If Deptford lost the 1x spare and got nothing in return, they could cope with a bit of a struggle like Percy Main have. Look at the Prince Bishops and that is running at a ratio of 10:1 with Streetlites.
Plus percy main are already running 1 double decker short as they lost 3859 and got nothing in replacement