The Hemmings article said
"Mecum’s online catalog lists the pre-auction estimate at $1,250,000 to $1,750,000, making this a sale for the most serious and well-heeled of muscle-car collectors. In an unusual move that we applaud for its transparency, Mecum also lists an “announced reserve” of $1,100,000, giving a very clear and distinct floor to what it will take for this pair of pedigreed muscle cars to find a new home."
So they are estimating high, but did reveal the reserve so nobody thinks of getting these under a Mill.