Do I have to register for signature classes in advance and how many people can attend a class at once? No. Signature Classes are available to registered guests of 1440 only on a first-come basis. Class sizes vary based on the venue and current health and safety guidelines. While there is no need to register in advance, please check in with the instructor upon arrival to verify that you are a registered guest. We recommend arriving to your desired class 5-10 minutes prior to the start when possible to secure your place. Do I have to register for signature classes in advance and how many people can attend a class at once?