You didn't by chance change from a ship that has you disembark close to your cockpit (usually cockpit at the front / disembark point at the front landing strut) to one that has you disembark at the other end? That's the only time I noticed a slightly longer disembark screen time (with quite a few footsteps to be heard) so far.
i did, from a DBX to an imp. eagle, was fine in the dbx (rear exit) then i bought an eagle (front exit) and the black screens began, not had time to get on and switch ships again to check but could what you say happen in reverse due to a bug/glitch? as its been an enjoyable time re learning the game for the last few weeks i suppose im due a slap in the face somehow ><
edit, i put it down to lag at first (i use mobile broadband but wasnt having issues before) as the black screens take varying amounts of time and footsteps if that is indeed what they are, i too assume(d) its a audio file on loop,
someone suggested the black screen is intentional to prevent people having to walk around m ore as in star citizen, if thats true you should be fired & not be allowed to even clean whats left the industry's toilets (by that i mean their toilets are in better condition than the gaming industry these days)
edit, well a ding-dang-doo! soon as i switched back & disembarked from the dbx, instant again =D confusing because the amount of black screen would be appropriate for the time to walk to the back of a dbx, but needs a fiddling or adjusting for eagles at least