Just to be clear, we'll be considering this film to be set in Earth-TRN414, right? HBK123 (talk) 10:36, January 31, 2020 (UTC)
I'm not sure that's entirely clear yet, for all we know it may wind up being a completely unique timeline like Logan. -- Annabell (talk) 10:40, January 31, 2020 (UTC)
According to this interview with director Josh Boone, 20th Century Fox originally intended this movie to be in the same timeline as 'X-Men: Apocalypse' (as Boone put it), before they allowed Boone to make it stand-alone.