How to set rpi system time at MAVROS startup through Flight Controller GPS?

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I want to set a Raspberry Pi 4 companion computer running Mavros system time using the GPS time in my flight controller via mavlink. The issue I've discovered is I can't start mavros successfully unless the times sync up within a very short range, and if there is no internet connection mavros won't start. It only makes logical sense since there are two embedded systems connected directly to each other and the time is coming off of the GPS from the flight controller that mavros should be smart enough or have a module to set the system time on the Raspberry Pi.

Anybody have a solution? Thanks for any assistance you were able to provide.

Sincerely,

Aaron