1. A method of comparing biometric image data to a stored enrollment template comprising: collecting a set of biometric object image data for a biometric object image from a biometric object imaging sensor; storing the biometric object image data in a memory as an enrollment template for further comparison to find a match with subsequently imaged biometric object image data; collecting a subsequent set of biometric object image data for a biometric object image from the biometric object imaging sensor; updating the enrollment template; determining if a limited enrollment window remains open; and repeating the collecting of a subsequent set of biometric object image data step and the updating step if the limited enrollment window remains open, wherein the biometric object imaging sensor is incorporated into a user authentication apparatus providing user authentication for controlling access to one of an electronic user device or an electronically provided service.