DEERS System Outage: October 9 to October 11, 2026. The Defense Enrollment Eligibility Reporting System (DEERS) will be unavailable from Friday, October 9 at 6:00 PM PT (9 PM ET) through Sunday, October 11, due to a scheduled system migration led by the Defense Manpower Data Center (DMDC). milConnect will also be unavailable during this window.