I’m going to rise above all this, as I have had an important email query that needs to be answered:
Jolly interesting facts. What current supply system does the train use on the UK high speed section? And how did they fit the long trains into Leeds Station?
The voltage on the high speed sections (both sides) is 25kV AC (traditional TGV voltage). It is possible for both power units to have pantographs due to the length of the train; and in fact each has two – there’s a separate pantograph for 3kV DC (Belgium).
I must confess I don’t know how long the platforms are at Leeds, but I do know the units leased by GNER were only 14 cars long. I believe they were also accomodated at York and Doncaster. failfaneurope.net has several pictures of the GNER “White Rose” Eurostars, this one shows units at Kings Cross in both original and GNER colours! They’re now serving in northern France.