nächste freie Termine finden mysql [3]

$free_intervals = array();                                                      
$next_start = new DateTime('now');                                              
while ($next_start) {                                                           
    $row = mysql_fetch_array($result);                                          
    $start = $next_start;                                                       
    if (! empty($row['Anreise']) && ! empty($row['Abreise'])) {                 
        $end = new DateTime($row['Anreise']);                                   
        $next_start = new DateTime($row['Abreise']);                            
    } else {                                                                    
        $end = new DateTime('now');                                             
        $end->add(new DateInterval('P360D'));                                      
        $next_start = false;                                                       
    }                                                                              
    if ($end < $start) {                                                           
        continue;                                                                  
    }                                                                              
    $interval = $end->diff($start);                                                
    if ($interval->format('%a') <= 3) {                                            
        continue;                                                                  
    }                                                                              
    $free_intervals[] = array(                                                     
        'start' => $start->format('d.m.Y'),                                        
        'end' => $end->format('d.m.Y')                                             
    );                                                                             
                                                                                   
    if (count($free_intervals) >=6) {                                              
        break;                                                                  
    }                                                                           
}