It has been announced today (13 March 2020) that the elections for the London Mayor and the London Assembly together with other local elections within England have been postponed for a year until May 2021. The BBC have reported that the Cabinet Office will be bringing forward legislation to enact the delay in England. This is as a result of COVID-19.
This means that Sadiq Khan will continue as London Mayor for a further year, giving him the opportunity to personally oversee the changes to the Low Emission Zone scheduled for October 2020.