Our cycle does not have the technology to travel intergalactically. Nowhere even close. And yet somehow within two years we figure it out, and built not only one but multiple drives capable of that and massive Ark ships to put them in, all in complete secrecy.
I have an issue with that being the reason for this entire mission.
Well I agree with that but it's not happening after the Reapers , I guess leaving before ME3 ending and waking up hundred years after the fact with no way to contact the milky way will take care of pretending nothing blue , green or red happened.
But anyway about the technology , it will pop up anyway because the Ark are a thing.
There's no point in saying it was a known project because in ME3 no one knew and secret project is conveniant to explain in secret some scientist figure out how to build Ark (perhaps stealing some Reaper technology) and secret project make sense with the Reaper threat , I assume the Reaper weren't about to throw a goodbye Ark party with champagne and present .