Changes in December 2009
Between Hammersmith and Edgware Road, the service was supplemented by Circle line trains from 13 December 2009, when that route changed from its previous orbital route. This was intended to cause fewer delays since, under the previous Circle line arrangements, one delayed train would affect all following trains. LUL claimed that having a terminus at Edgware Road, rather than the continuous orbital route, would avoid this.
The Hammersmith & City line continues to run as a separate entity, with trains running to Barking and Plaistow in the east. The headway on the Hammersmith – Edgware Road leg has been reduced from seven to four minutes by this schedule change, and the alternation of Hammersmith & City with Circle trains now in principle provide 12 trains per hour at peak times on this section, doubling the previous frequency.
Read more about this topic: Hammersmith & City Line