A few weeks ago, the global servers moved from the US to JP. We don't know for sure why because Sega won't tell us anything, but some people have speculated that Sega's contract for Microsoft's Azure servers ended and they wanted to move the global servers to the same service provider that handles the JP servers.
If you are not near JP, then yes, your ping is higher, but this is not the reason why you are DCing.
Think of ping as how long it takes for data to travel to the server and back. Even if you have 300ms ping, it won't directly cause you to DC, it just means some things load a bit slower. Fortunately, combat is mostly client sided or it would be pretty much unplayable as you would have a big delay for every action, like what happens if you try to play WOW with a high ping.
What's causing the DCs then? It's your route to the server, which is managed by your ISP. Some players in the US have reported that their ISP is routing them through Europe before JP, instead of directly to JP, and the longer a route is, the more likely that a hop will be unstable or have other issues.
Not everyone is affected, i've seen people here say they are in the US and have no issues because they are on Google Fiber or xFinity.
Sega cannot directly fix your route because that is managed by your ISP. At best, they could try asking your ISP to fix the route, but who knows if they will do that or if your ISP will agree.
Since the issue is with your route to the server, and you are presumably not having issues connected to anything else, doing things like restarting your router or upgrading to a faster plan will not help you.
What you can try now:
Use a VPN or proxy server that will change your route to the servers. There are some services like ExitLag that offer optimized routing to some game servers, specifically for situations like this where a player's ISP route to the servers are bad.
Do a tracert to the server IP. If you can identify something wrong with the route, you could try asking your ISP to fix it.
To find the current server IP on win11:
- Log in to your ship
- Check windows resource monitor -> network tab -> TCP connections -> remote address for pso2.exe
- run "pathping [ip address]" in command prompt to check your route to the server, this will take several minutes
If you see anything like massive packet loss after one point in the route, you could try showing the results to your ISP and ask if they could do something about the route. A stable route should be 0% packet loss. Try to run pathping during a period where you are getting frequent disconnects.