heating, seating and Wi-Fi was completed in December 2016. Class 321/4 In October 1988 a second batch of 30 was ordered. It was intended that 25 be used on Great Eastern Main Line services and five on West Coast Main Line services, but in the event all were delivered to Bletchley TMD for use on the latter. A further 18 followed. Units were numbered 321401–321448. The first was delivered in July 1989. These were built for outer-suburban services on the West Coast Main Line, from London Euston to Northampton, Rugby and Birmingham New Street. They displaced the then-recently cascaded Class 317s dating from 1981 which had themselves only just been introduced to the route to replace Class 310s. Eleven 321/4s were transferred for Great Eastern Main Line services. Following this, their First Class area was reduced in size to standardise with the 321/3s in use on that route. This involved removing the centre partition and double doors and re-upholstering the First Class style 2+2 seats (which were retained then) in the de-classified area into the same fabric as the Standard Class seats. Later the First Class 2+2 seats in this de-classified area were replaced with the standard style 2+3 seating. These 11 were also fitted with a facility to lock out the power door operation within the unit (a basic kind of Selective Operation) to permit operation of 12-car trains on the Braintree and Southminster branch lines, where some platforms were only long enough for 8-car trains. The 11 Great Eastern sets passed to First Great Eastern in January 1997, passing with the franchise to National Express East Anglia in April 2004 and Abellio Greater Anglia in February 2012. The 37 West Coast sets passed to Silverlink in January 1997, passing with the franchise to London Midland in November 2007. In 2006, 321407 and 321423 were loaned by Silverlink to Northern Rail while the 321/9s were being overhauled. In 2007, 321408 and 321428 were loaned by Silverlink to c2c operating services out of Fenchurch Street while one Class 357 was repaired and another was undergoing tests in the Czech Republic. Following the delivery of the Class 350/2 fleet, 13 Class 321/4s (401–410, 418–420) were transferred from London Midland to First Capital Connect and overhauled by Wabtec's Doncaster Works. These passed with the franchise to Great Northern in September 2014. London Midland also released 17 (421–437) for transfer to National Express