were suspended by Transport for London in November 2011 due to concerns over reliability. A number of trains were delivered to London Underground's Neasden Depot, but were not accepted to enter service. Deliveries resumed in mid-December 2011. In August 2012, London Underground confirmed that strap handles would be introduced on S8 Stock, in response to passenger complaints over the height of the handrails as compared with A Stock. By 15 September 2012, all 58 S8 trains had been delivered to Neasden Depot. The A Stock trains were completely withdrawn 11 days later. In November 2012, it was reported that 37 of the new trains would be sent back to Bombardier for urgent modification at Bombardier's cost, and that drivers were unhappy with their cabs. An additional S8 train was later delivered, as part of the subsequently cancelled Croxley Rail Link project. Hammersmith & City line The first trains entered service on 6 July 2012, from Hammersmith to Moorgate. S7 trains are longer than the C69 and C77 trains they replaced (seven cars and long instead of six cars and long), so some station platforms had to be lengthened to allow for S7 operations. For stations where this has proved physically impossible, such as , the trains have a selective-door-opening capability whereby the doors at the end of the train will not open. On 4 December 2012, an S7 train went east of Moorgate to Barking for testing. This was the first time an S7 train had been seen in peak hours. S7 Stock began operating a full service from Hammersmith to Barking on 9 December 2012. The line was completely operated with S7 stock from 11 February 2014. Circle line The S7 Stock entered service on the Circle line on 2 September 2013, and completely replaced the C Stock trains on the line by 11 February 2014. The Circle line's C Stock were replaced ahead of the District line's D Stock, as they were described by London Underground as being "in an increasingly poor state", and the D Stock had been extensively refurbished between 2005 and 2008. District line The District line was the last line to be fully served by the S7 Stock, due to its existing D78 Stock being newer than other trains that the S7 Stock was ordered to replace, as well as its most recent refurbishment in 2005. The first S7 Stock train entered passenger service