[2][3] In November 2003 the Strategic Rail Authority awarded the new franchise to First with the services operated by Thames Trains transferring to FGWL on 1 April 2004.

The Stratford-upon-Avon service was transferred to Chiltern Railways in December 2004 with FGWL ceasing to operate beyond Banbury.

A franchise commitment was to use five Class 180 Adelantes from sister company First Great Western on Cotswold Line services from December 2004,[10][full citation needed] releasing five Class 165s for transfer to Chiltern Railways.

[11] Because of the short nature of the franchise and the fact that the Class 165s and 166s had only recently been repainted, the Thames Trains livery of white, blue and green was retained with FGWL branding applied.

This was part of a Strategic Rail Authority strategy to reduce the number of train operating companies providing services from a single London terminal.