Does the learner need their own insurance?
This is where things can become confusing.
When a learner takes a lesson in an instructor's insured tuition vehicle, the instructor's specialist insurance is designed for that tuition use. The learner does not normally need to arrange a separate insurance policy simply because they are receiving a lesson in the instructor's vehicle.
However, the situation changes when a learner practises outside their paid lessons.
For example, if a learner drives a parent's or friend's car for private practice, they must have appropriate insurance to drive that vehicle. GOV.UK advises that learners practising in someone else's car must either be covered by the vehicle owner's policy or have their own learner driver insurance.
This means learners should not assume that their instructor's insurance covers them when they drive other vehicles outside their lessons.