(03 Aug 2016, 8:24 pm)Andreos1 wrote  Where they the same batch to work what is now the X12?

I believe 4646-4659 were all based at Durham for services 43, 49 and X1 (X1 was what we now know as the X12) when they were new in 2005. Some later passed to Redcar for the 63 then later the 93/X93. Sometime in 2011, five examples transferred from Durham to Darlington for the X66, a further four came to Darlington from Redcar in 2013 when the X93 became double deck operated but four left Darlington not long after when the 13 reg Pulsars arrived. 4643/4644/4645 started life with Arriva in Liverpool.