The last two times I rode the Starlight, the "correct" procedure was board your sleeper,stash your stuff in your room,wait on the Conductor to Scan your ticket, and then once the announcements were completed, and the Train left the Station, one could move about the train.
The PPC Attendant told me to return to my room and wait for an announcement,that they weren't "Open" yet, when I went to the Parlor Car to inquire about Meal Reservations and to try and snag a Swivel Chair on the "good" side,ie the Left for the Ocean View.YMMV