Brooklyn gets very crowded early and there is very little room to wait, and there are not enough seats. I do not know that wheelchair assistance is provided until you are past the security line, though I do know that folks in wheelchairs are given priority through security. There is a desk in the entry and those folks can likely help, but I strongly urge you to try to arrive closer to your time so that everything is up and running. You will have less waiting around time than if you show up at noon.