It depends on how the dealership codes its grounded loaners. At mine, they would 'purchase' the loaner, then do the CPO process and sell it has a certified used car. This way it would get all of the benefits of the Mazda CPO program. Most Mazda dealers around here do it that way. When I was at Chevy, they would just take the grounded loaners and put them with the 'new' inventory and sell them as new with only the standard new car warranties, but with a little more rebate money from the factory