I am trying to apply vCenter standard license to vCenter which has Essentials Plus license already applied. I can add the these licenses into the vCenter but when I try to apply to vCenter with standard license I get following error "The host is licensed with VMware vSphere 5 Essentials Plus. The license edition of vCenter Server does not support VMware vSphere 5 Essentials Plus". Also, ESXi hosts gets disconnected. So I tried to apply enterprise plus license on ESXi hosts just in case ESXi hosts needs to be licensed first but that also failed with similar error and hosts gets disconnected.
Can you help with understanding why I cannot apply vCenter standard and Enterprise plus license on the hosts/vCenter which has Essentials plus license applied? Also how can I apply vCenter standard and Enterprise plus?
FYI - it is vCenter 6.5 and 5.5 ESXi environment.