Another article said it was a South Dakota Guard jet, but pilot was a California 144th FS guy.
Made me think “ferry flight.” Maybe a jet swap, depot, who knows.
I think the cordon and hazmat caution is for the Hydrazine that the EPU uses in event of generator failure. Hydrazine exhaust/spilled combustion fumes are pure ammonia, and cause fatal lung injury if inhaled.
And, most fighters with a cannon are flown with a full or mostly full magazine of shells for weight and balance purposes. The M61 Vulcan varies by aircraft type on capacity, but I think the F-16 is in the 500+ round range.