The notice reads, " ... may have a condition where contamination in
the brake light switch could cause the loss of brake lamps or
continuous illumination of the brake lamps. The performance of the
brakes is not affected."

Next paragraph: "Do not take your vehicle to your Chevrolet dealer as
a result of this letter unless you believe that your vehicle has the
condition as described above."

OK, so the left brake lamp and the upper brake lamp work fine, but the
right brake lamp is out.

Would you say that this is more likely a burned-out bulb rather than a
contaminated brake light switch? With a malfunctioning switch,
wouldn't all three brake lamps fail? Thanks.