Haven't seen it yet and don't want to spoil it viewing too many trailers, sorry, but my guess is it wouldn't matter anyway as stars occupy three dimensional space and once you move in any given direction the star maps will alter accordingly. Plus clouds of gas and dust obscure certain objects whilst others are revealed, it would be very hard to tell.
So, they could be looking at what may well be totally 'made up' star maps but is simply what we would see viewed from a different part of he galaxy?
You would need a very good three dimensional computer simulation model to be able to work it out anyway.
I suspect we will get to find out via some future sci-fi convention/interview with input from someone on the production crew.
They usually blab in the end.
