McDonald’s is calling on all of its US restaurants to open at 5am in order to meet the increasingly earlier breakfast times of customers. About three quarters of the chain’s 13,700 US restaurants already open at 5am, but a company spokeswoman said the group would like to standardise the start time. The spokeswomen said: “Customer lifestyles continue to change, and commutes are becoming longer. There is an opportunity to serve either earlier or later.”