SW Upgrade Failed after download - SW File corruption

Getting this message on my CAX80: SW Upgrade Failed after download - SW File corruption

Log notes Config file s11_m_cax80_superfast_c01.cm

this causes the router to crash, and requires at least 2 reboots (with long load times) before it comes back - and in at least one case I have to reload settings from a backup before it started working. How can I block it from attempting to update?