Classic master cylinder failure mode, or a split/bad leak in two brake hoses.
How was the bi-annual brake flush done, if the pumping the pedal method was used, the seals in the m/c are probably shot. If the bi-annual flush was not done, probably the moisture has gotten to multible calipers and it is time to renew your brakes.

What is the mileage and weather like where SAV is operated, will help more with diagnostics.

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