The covered dependents may continue coverage for up to 36 months from your Medicare entitlement. You must provide documentation of Medicare entitlement to Benefits Administration before the end of the 18-month extension. If you or your dependent is entitled to Medicare or enrolled in another group health plan at the time you experience a qualifying event, you may enroll in COBRA coverage. However, an employee continuing coverage through COBRA who later becomes entitled to Medicare or enrolls in another group health plan may no longer continue COBRA coverage.