Behavior in Central of servers booting from a master image

Hi, I would like to understand the behavior of servers within Central when being deployed from a master image. We have followed the KB article to allow this to happen but it appears to react in not the way I was expecting.

We have around 100 Citrix virtual servers, all booting from one master image. When one virtual server is using this it, is fine. The server appears (alongside the master image) in Sophos Central, as a separate entity.

However, when we introduce more than one virtual server something happens. The first virtual server we power on takes over the master image in Central - all other servers we then boot are duplicates of this server and Central de-duplicates them. The de-duplication is successful and from our testing appear to work ok.

My question though is, shouldn't the KB article stop the servers being picked up as duplicates in the first place? The above could cause confusion as our master image is named incorrectly as a virtual server.