I was watching the terminal where 343 says maybe the flood is waiting outside the galaxy…OR WORSE, DRIFTING TOWARDS US. Does this not seem strange to put in if it does not happen in H4?
This is not new information. We already knew the Flood were of extragalactic origin. I believe Spark was simply speaking of the reasons why samples were kept and not it being any form of clue.
The only thing I believe that could be connected directly to Halo 4 in the CEA terminals is the crashed alien ship.
He also says that if the Halos were turned against them, there would be long plans, indeed, which I think is hinting towards Halo 4’s story. Maybe the Halos will be turned against the Forerunners.