JCS Online Resources is just the sales agent for British Newspaper Archive so we linked you up with their help desk. But I can confirm that the reason you're experiencing these error messages is because BNA doesn't support OpenAthens. Access to BNA is only via fixed IPs aand not off-site. So as long as you are using BNA from a computer running from one of your registered IP addresses you'll be able to perform all the searches you want to make but not otherwise.
Hope this helps
Director, JCS Online Resources
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