So with no online status updates since submitting EOI in June, I again contacted INZ to enquire as to why i am unable to see my ITA status in my online profile. I recieved this reply which does not explain why some people can. Any comments appreciated.
While an EOI is the first step under the Skilled Migrant Category process it does not necessarily lead to an ITA or subsequent application and consequently sits in a separate Online Services system from the status check. As specified in my previous response, the status check functionality has recently been discontinued.
Unless you have registered for online viewing of visa application (not EOI) status previously you will not see your resident visa application status when you log in to your Online Services account.