Drivers have appeared in courts in the last month charged with speeding on the M4. Although the maximum speed on the motorway is usually 70mph, the limit has been reduced to 50mph on some stretches of the road while works to upgrade it to a smart motorway are carried out. The following drivers were charged with exceeding a temporary speed restriction on a motorway. Emma Louise Kerr, aged 22, of Dovetail Close in High Wycombe, was caught driving a Toyota Aygo at 68mph between junction 8/9 and junction 10 on October 10. At a hearing at Oxford Magistrates Court on May 5, she was fined £440, told to pay £134 costs and given four points on her licence.