Buried in this Empire feature about The Martian:
There were also earlier rumors that he'd start production in January and that he was asking Fox to hold off on Neil Blomkamp's Alien sequel until Prometheus 2 was released.
They faced another challenge when the films release date was brought forward. But according to Damon, the typically fast-working Scott didnt worry. Ridley was done with the movie about two weeks after we shot! he smiles. I was already on to my next movie! adds Scott. I was starting to look for locations for my next movie, which is Prometheus 2.
There were also earlier rumors that he'd start production in January and that he was asking Fox to hold off on Neil Blomkamp's Alien sequel until Prometheus 2 was released.