When may you reverse from a main road into a side road?

You may reverse from a main road into a side road when it is safe to do so, ensuring that there are no oncoming vehicles or pedestrians. It's important to check your mirrors and blind spots before reversing and to signal your intentions to other road users. Additionally, this maneuver should only be performed when it does not disrupt traffic flow and is compliant with local traffic laws. Always prioritize safety and caution.