meta_query orderby sort multiple keys

Question

I'm trying to read the birthdays of the users in my database through custom fields that have been added. Displaying the current months is easy but I am trying to capture the current month(remainder) and capture part of the next month (10-15 days) based on the current day. I don't understand how to order by the current months and days so they are in ascending order. Not sure if the issue is something in my arguments or something I should be doing in my foreach loop. I could sure use some help trying to understand where I'm going wrong or if my approach is wrong. Thank You.

$current_month = date( 'n' ); // 1-12
$current_day   = date( 'j' ); // 1-31    
$next_month = date('n', strtotime('next month'));
$day_span = 28 - $current_day;

$args_birthday_current = [
'role__in' => ['subscriber'],
//'order' => 'ASC',
'orderby' => ['birth_day' =>'ASC', /*'birth_month' =>'ASC'*/],
'meta_query' => array(

    'relation'  => 'OR',

    array( 'relation'  => 'AND',

        'birth_month' => array(
            'key'       => 'birth_date_month',
            'value'     => $current_month,
            'compare'   => '=',
        ),

        'birth_day' => array(
            'key'       => 'birth_date_day',
            'value'     => $current_day,
            'compare'   => '>=',
        ),

    ), 

    array( 'relation'  => 'AND',

        'next_month' => array(
            'key'       => 'birth_date_month',
            'value'     => $next_month,
            'compare'   => '=',
        ),

        'day_span' => array(
            'key'       => 'birth_date_day',
            'value'     => $day_span,
            'compare'   => '>=',
        ),

    ),
), 
];

My Loop

foreach ( $user_query->get_results() as $user ) {

    $birth_date_month_number = get_user_meta($user->ID, 'birth_date_month', true);
    $birth_date_day_number = get_user_meta($user->ID, 'birth_date_day', true);
    $birthday = date('F jS', mktime(0, 0, 0, $birth_date_month_number, $birth_date_day_number, 0));

    $user_id = "user_".$user->ID;
    $badge = get_field('user_profile_photo', $user_id);
    echo '<a class="profile-link" href="profile-page/user/index.php?user=' . $user->last_name . '"><div>';
    echo '<div class="thumbnail-wrapper"><img class="img-fluid small-thumb" src="' . $badge['sizes']['thumbnail'] . '" alt="' . $badge['alt'] . '" /></div>';     
    echo '<div class="profile-wrapper">' . $user->first_name . ' ' . $user->last_name . '<br>' . $birthday . '</div>';
    echo '</div></a>';
}