Simply put, Lin Fan had two reasons for acting now.
First, the Black Mang Empire used a combination of Fault Channels and Black Hole Engines. As long as they grasped its route, they could choose a suitable location to ambush it, much like the currents between superclusters in the universe.
Of course, generally speaking, God-tier Civilizations would not directly choose the shortest route, because that would make it too easy for their opponents to predict and ambush them. Instead, they would use different combinations of Fault Channels along the way. At most, it would waste some time, but it was safer.
However, this approach was useless against the Federation. The scanning equipment within the Life Transcendence Device could scan an area of ten thousand Standard Black Hole Units around it. It was equivalent to an ultra-long-range radar that made their every move plainly visible.
Second, they could take advantage of the Black Mang Empire being locked in a stalemate with the Hiltek Empire and set its backyard ablaze, preferably even drawing the Tailo Empire into invading it.
That way, the Black Mang Empire and the other two God-tier Civilizations would have no time to attack the Azure Dragon Universe from this direction for at least several hundred years.
As for several hundred years later...
Well, forget several hundred years. Given less than a hundred years, Lin Fan was confident he could turn around and crush all three of them.
Furthermore, the Federation could use this period to peacefully develop in other directions, occupying large numbers of universes to strengthen its foundations.
"Since no one has any objections, I'll explain the arrangements for this operation!"
"First..."
Federation Year 295.
The Stoke region, more than 9,000 Standard Black Hole Units from the Azure Dragon Universe.
A massive fleet stood arrayed there.