What is the primary focus for hardening the upper stage following this anomaly?

Answer

Hardening against non-propellant-related over-pressurization events during hold phases

The primary takeaway for the program is the need to increase safety margins and hardening specifically around ancillary systems to prevent over-pressurization events originating from non-propellant components while the vehicle is holding prior to ignition.

What is the primary focus for hardening the upper stage following this anomaly?
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