Intermittent WP7700 module Failure: [Fatal error on the modem]

Asyal,
Thanks for hte suggestion - precisely what I planned for 1st thing this morning - get a baseline.

I’ve reflashed the modem firmware (ATT v9.1) - with no change.
I’m not quite clear on a baseline build to load - or if the Recovery Procedure is what you imply.
(incidentally per Shib’s recommendation I have built with the latest Legato 18.10.3).

Appreciate any clarity/pointers,
Mike