i contacted lexus regarding my 1st mot and if it failed on a part under warranty if i would still be covered, here is their reply
Thank you for your email regarding your Lexus IS300h.
Lexus UK would like to reassure you that for the foreseeable future, we intend to take a flexible and sympathetic approach to any service schedule or warranty issues which may arise due to delays caused by the COVID-19 outbreak. My only recommendation would be to book your car in with your Lexus Centre as soon as business returns to normal to have your service and MOT work carried out, as oppose to waiting for the full 6 month period until the "new" MOT expiry date. Of course, we do not know when this will be yet, which is why we aim to be as flexible as possible with our customer's where we can.