Learner drivers and Motorways

[osprey]

Is it illegal for (a) learner drivers to use motorways and (b) driving instructors to use motorways whilst displaying their rooftop advertising signs? I have always thought that both were illegal.

[redcrx]

learner drivers cannot drive on motorways. But i suppose a driver taking an advanced course after passing their test may well be using an instructors vehicle to take the course in

[sddsddean]

Car/bike learners can't use M'ways, but LGV and PCV learners can. I don't know if there is a specific rule that an can't be displayed by cars, but it may help indicate that it is an inexperienced driver getting motorway tuition after passing their test.

[Panic Button]

Quote from the learner driver requirements section at the end of the Highway Code:

Plates should be removed or covered when not being driven by a learner (except on driving school vehicles).