OK, you go to your design and set bottling date. How does BeerSmith use that date to adjust your fermentation profile? Does it lop days off or add days on to your primary fermentation? Your Secondary, if there is one? Your cold crash?
BeerSmith is designed to be modeling software. It can only respond to the inputs you give it in terms of materials and process. Inputting a bottling date only gives it an output result and not how you arrived there.
OTOH, it would be good to have some sort of monitoring page to input actual temperatures, times and checked gravity versus the profile the program is presented with.