There is a lot of unexpected lag on the 1.13.1 server. At this time we are not sure why the server is struggling to run on 1.13.1 when it was running just fine on 1.12.2. It will likely take some time for us to fix. We first need to watch the server’s performance during normal operation carefully, taking reports of RAM utilization, CPU usage, and network bandwidth. At this time I am attempting to figure out how many players the server can handle so that I can set a safe player limit.
Note: until we figure out the source of this lag, we are disabling donor’s ability to join when the server is full. This must be done to prevent the entire server from grinding to a halt and freezing up.