Here's the official EHE guidance for England:
2.7 There is no legal definition of “full-time” in terms of education at home, or at school.
Children attending school normally have about five hours tuition a day for 190 days a
year, spread over about 38 weeks. However, home education does not have to mirror
this. In any case, in elective home education there is often almost continuous one-to-one
contact and education may sometimes take place outside normal “school hours”.
2.8 Home-educating parents are not required to:
• have a timetable
• set hours during which education will take place
• observe school hours, days or terms
2.9 In practice, the question of whether education for a specific child is full-time will
depend on the facts of each case; but you as parents should at least be able to quantify
and demonstrate the amount of time for which your child is being educated. Education
which clearly is not occupying a significant proportion of a child’s life (making due
allowance for holiday periods) will probably not meet the s.7 requirements.
Sometimes an average day for us here looks like DD spending an hour or two sat down working on Sociology practice questions, followed by English, followed by Maths, followed by something else. Sometimes it looks like twenty minutes of maths, then bouldering class, then music practice, then working on a Girlguiding badge, then theatre group or Guides in the evening. Sometimes it looks like leaving first thing in the morning, spending the entire day out somewhere, then coming home with zero paperwork done. All of those are educational. The LA is aware of what our days look like, and have assessed us as providing a full time, suitable education.