The first vehicles were originally due to be delivered to the British Army in April 2017, however this was delayed. In May 2020 it emerged that the delivery of the first batch of Ajax vehicles was to be delayed further as they were found not to be ready to be accepted into service. It is not exactly clear what caused this delay but, in its evidence to the inquiry GDLSUK stated that delays had occurred in agreeing requirements and challenges with the integration of the 40mm weapon system mandated by the Ministry of Defence - similar to the issue on the Warrior programme.