Wakapedia:
โ Our goal is to have another Tech-Preview Server Meshing test for select waves of testers (Multiple Waves) starting on Friday and running through the weekend. This Server Meshing test will be focused solely on the Stanton system, with multiple servers sharing the load. We will be testing multiple configurations throughout the weekend with more servers per shard than we have ever tested before, increasing the number of players per shard to stress test the system.
This will not be just evocati.
https://robertsspaceindustries.com/spectrum/community/SC/lobby/38230/message/52087974
I'm guessing that we will most likely see servers covering each major zone throughout the solar system that includes at least one planet. If things are looking good they might take it further than that.
The entire goal of Server Meshing is fixing the "existing 100 player ones barely function" issue. Server Meshing breaks a single logical "server" into multiple backend servers that are all meshed together to provide a consistent and transparent experience. A 400 player server could actually end up being 10 backend servers, with 40 players each. Thus, it'll run much better.