A number of small publishers I've worked with in recent months have seen their access to Facebook Instant Articles removed by Facebook. In all cases, the only warning they got was a message along these lines on the Publishing Tools page of their Facebook Page:
Or, in a couple of cases, this:
The latter, ironically, appeared following a period of time when Facebook stopped accepting Instant Articles delivered via the API from the publisher's CMS for no clear reason.
The withdrawal of Instant Article privileges seems to be based on this clause of their guidelines:
We may reduce your article's distribution in News Feed or prohibit you from using Instant Articles if you become inactive, have minimal readership, or if the content on the web version or your article contains ads that provide an unexpected, disruptive, or misleading experience. This includes apps and sites that contain a disproportionate volume of ads relative to content, or ads that drive a negative user experience such as ads that are highly sexual, visually shocking, or promote scams.
Interesting that they equate low traffic sites with scam sites, isn't it?
However, none of that changes the fact that Facebook have pulled the plug on a facility that small publishers have spent time and money to implement on their sites, without warning, and without any clear guideline of what "minimal traffic" actually is. As well all know, there are some very small volume traffic sites that are very valuable, because of who their traffic is coming from…
Yet another example of why publishers should never trust Facebook.