Group adjustment LBY sets lobby floor, that’s where it’ll park.
Group adjustment LER sets # of cars requested to lobby.
I don’t think you can put a delay on that.
If you really want a delay you could probably setup zoning but I’ve never tried on a TAC20. I think you’d set CSW bits 4 & 5, set NZN to 1, ZN1 to the floor you want to park at, then set the delay with PFT, Parking Free Time. For a duplex maybe set NZN to 2 and set ZN1 and ZN2 to 2 floors that would be okay for the cars to park at.