What should you do if a lorry approaching a turning indicates left but moves right?

Explanation: When a long vehicle is going to turn right, it may need to keep close to the left-hand kerb. This is to prevent the rear end of the trailer cutting the corner. You need to be aware of how long vehicles behave in such situations. Don't overtake the lorry, because it could turn as you're alongside. Stay behind and wait for it to turn.

Category: Other types of vehicle (Motorcycle Theory 2021)

References: The Official DVSA Guide to Riding: Section 10, Highway Code: Rule 221