The FTSE 250 index was unchanged at 19,607.61, with luxury car maker Aston Martin Lagonda the biggest riser after a surge of 3.3p to 73.5p. Telecom Plus, which trades as Utility Warehouse, improved 36p to 1,402p as it reported marginally better half-year profits and said it had seen a return to customer growth in the second half of the year.