Global Entry isn't a forever thing. It has to be renewed every 5 years by your birthday. Approximately 5 - 6 months before your birthday you'll receive an email asking you to fill in forms (such as countries visited in past 10 years and other forms you filled in initially and pay another $100.00. Once everything is accepted you'll get another email asking you to select an airport and pick a time for the interview. It's an easier interview than the initial one and they take new fingerprints and photo.
Jim