If I'm honest, I had mixed feelings about the 20 Voyagers going to XC from Avanti.
However, capacity is what's desperately needed.
If it was me I'd be very tempted to do this: Transfer the 20 Voyagers from Avanti to XC and, in turn, run 5 x 10-car Voyagers on the HST diagrams, use the HST's on the 5-car Voyager diagrams, use the 5-car Voyager diagrams on the 4-car Voyager diagrams then use 4-car Voyagers to make 8-coach Voyagers.
One HST diagram I'd have as a result would be the 08:37 Penzance to Glasgow Central - on Fridays (jot sure about other weekdays), I've seen that reported full on Twitter. Not surprising as the train runs through the South West in the morning, Bristol at lunchtime and Cheltenham just after lunch. It also arrives in Yorkshire mid to late afternoon plus Newcastle at tea time and Edinburgh around 19:10.
An HST on the 08:37 Penzance to Glasgow would also allow an extra 2 hours for the train to get back to Edinburgh.
Sorry if I've mentioned this next bit on here but a member of XC staff told me on the 02/01/20 that we're getting Virgin's Voyagers - obviously Virgin is now Avanti.
You watch, just as many of us will be happy and settled with the idea of Voyagers from Avanti will not be happy if it's said we have to wait for new trains in say 2024 to solve the XC capacity crisis

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