What counts as the hours in a school day?
The time from the official start of the school day (morning registration), to the official end of the school day for all pupils (official home time). It includes breaks, lunch, teaching time and any enrichment activities that pupils are expected to attend.
It doesn’t include optional before or after school provision.
Mainstream, state-funded schools should provide a 32.5-hour week
The DfE expects all mainstream state-funded schools to provide a 32.5-hour week (or 6.5-hour days) by September 2024.
It has published guidance and case studies to help schools achieve or exceed this expectation.
This is not a requirement, but Ofsted will consider it as part of its 'quality of education' judgement (see page 5 of the guidance linked above).
It's likely you already provide these hours, so won't have to make any changes to meet this expectation.
This expectation does not