You are right in that it would be disrespectful to make an appointment with one girl and flake on her in favor of a different girl. If you would prefer to speak with them in person then your only real option is to show up and speak with whomever is available. That said, all of our ladies are both incredibly attractive and have wonderful personalities. If someone that you had your eyes set on is unavailable then meet the others. There is no doubt in my mind that you will find someone perfect for you and who will give you an amazing time.