Metropolitan Line: SEVERE DELAYS between Baker Street and Harrow-on-the-Hill, and MINOR DELAYS between Aldgate and Baker Street due to a signal failure at West Hampstead. MINOR DELAYS between Harrow-on-the-Hill and Amersham / Chesham / Watford due to an earlier signal failure at Chalfont & Latimer. Tickets are being accepted on London Buses. GOOD SERVICE on the rest of the line.