Couch bed support on 3023 or 3124KB

OK guys, pull out your couch bed seat and tell me if there is structural support from the floor and wall that the underside of the cushion frame would rest on that keeps the seat from sagging in the middle.

I have a new 3023 with a 40 gallon water tank and I could have sworn I saw a center seat support on a 3023 with a 20 gallon tank. Our 3023 with the 40 gallon tank has no such support.

Thanks in advance....

Flycaster