There are two types of flushes. One is simply dropping the pan and letting the fluid flow , the other is doing the actual flush where they drop the pan, let it flow and put it in drove to cycle the old fluid out.. Either way, they are both called flushes. The former is the cheap way to do it and no reputable dealer would it that way.
Look up above for my description of how a transmission flush is done. Yours is incorrect.