Complex sentence: On 6 June 1987 the route was extended on Sundays from Highgate Village to Hendon Central to cover the withdrawn part of route 143, although this extension only lasted until 2 February 1991.
Split into simpler sentences: On 6 June 1987 the route was extended on Sundays from Highgate Village to Hendon Central to cover the withdrawn part of route 143. Although this extension only lasted until 2 February 1991.