arm_before_update_user_subscription

This action will be executed just before user's membership plan will get updated.

Hook Type: Action
Usage:
add_action( 'arm_before_update_user_subscription', 'your_function', 10, 2);
function your_function($user_id = 0, $new_plan_id=0) {
    //Do Your Action
    //$user_id User ID.
    //$new_plan_id New Plan ID.
}
Parameters:
$user_id
User ID
$new_plan_id
New Plan ID