Diamond and Platinum guests are able to do online check in 16 days before sailing. All other guests can check in 14 days prior to sailing. You will pick your port arrival time during the online check in process. Based on the order of check in, you will be assigned a boarding zone which will be printed on your boarding pass. Once they begin boarding, they will board Suite guests and then begin calling boarding zones starting with A1. In order to get the earliest boarding time possible for you, complete your checkil in the minute it is available for you which is 12 am ET either 14 or 16 prior to sailing depending on your status. Hope this helps.