nah, I don't think this is right. The thursday preview was always historically midnight (or technical 00:01). This was then moved to ~19:00 local time to get better turn out. But it was still a preview. Star Wars did bump this... because the 19:00 shows just got obliterated in attendance.. but really.. outside of star wars, where do people really see 19:00 shows being obliterated to the point of getting away with 22:00, 01:00, 04:00, etc. showings then being added.
of course they could also just get stupid about it. but right now I'm going to say that the preview number, friday number and opening day number will probably stand for a while. well, at least to episode VIII. I do think Ep VIII will likely break this one's due to both the goodwill and being the actual 40th anniversary.