For me
TPE
5 sets remain with TPE to run York - Scarborough shuttles with the odd run to Leeds via Methley. ECS to and from York depot to satisfy the Scarborough depot mob
Therefore core Scarborough and York crew knowledge only so easier to train
Chiltern
5 sets to run as now, they know the 68s so only have to train on the slight differences between the two
Full training on mark 5s
Others
3 sets in a neutral livery to run on either TOC along with the spare DT
TPE
5 sets remain with TPE to run York - Scarborough shuttles with the odd run to Leeds via Methley. ECS to and from York depot to satisfy the Scarborough depot mob
Therefore core Scarborough and York crew knowledge only so easier to train
Chiltern
5 sets to run as now, they know the 68s so only have to train on the slight differences between the two
Full training on mark 5s
Others
3 sets in a neutral livery to run on either TOC along with the spare DT