Clusters are basically instances which are split up using grid transfer plugin.
0.1 – is the Transfer Hub for the PC instances which are 1 -6 which are PC only instances
7 – 7.5 are Cross Platform instances which use the EOS. Players who join these worlds will be on EOS servers not STEAM servers.
You will be able to tell which cluster you are connecting to by looking at the server info. STEAM will show an IPV4 address where EOS will show a IPV6 address
