In each of the following situations, state at which date(s), if any, revenue will be recognised. Explain your reasoning.

A contract for the rendering of services is entered into on 1 May 2023. The services are delivered continuously over a 1-year period commencing on 15 May 2023. The buyer pays for the services on a monthly basis, commencing on 15 May 2023. The buyer may revoke the agreement at any time.