Errors when bot supplies its own session ID?

Duh, sorry, not thinking today. I hate it when something works as it should, but doesn't give a clue why it changed.

If the robot visits your site, thus triggering a new session, it can read the session ID but still triggers a session test within seconds of the first. I don't know enough about how a typical robot is coded to know why that would happen. A question becomes: is it the robot that is triggering the second session check or is it done by CI?

CI 3.1 Kubuntu 19.04 Apache 5.x  Mysql 5.x PHP 5.x PHP 7.x
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