This has been floating around since late February now, but the gaming sites are only just now deciding to comment on it. Apparently because the original reddit thread whence it first appeared has been taken down, suggesting spoilers are real. I recommend taking this with some huge grains of salt.
A video back in late Feb from the Know, recommending salt and lots of it.
A video from Whatculture a few days ago, summarizing the contents of the reddit post (which has now been taken down).
The short version is that Insurgency is supposed to be an intraquel, set a few years after
Origins but still several years before
Asylum (and before the
Knight DLC known as
A Matter of Family, set not long before
Asylum.)
In terms of the (extended)
Batman: Arkham timeline, this means we can expect the origin of at least one of the Robins (Grayson or Todd, not likely Tim Drake), but not the Killing Joke plot nor even Gordon becoming Batgirl (because
Matter of Family, several years later, was close to her first adventure as Batgirl -- she had rescued her dad at least once before then if I recall correctly).
Supposedly there will be an announcement about this at E3 coming up. If the list is accurate (massive salt, massive salt), I'm okay with it in principle, but it sounds a lot like filler where a dev team takes the
Knight engine and all art assets up to now for a repurpose cash grab. Some of the rogue gallery on the list sounds meh, too.