Amputee Marksman
NES Member
How often where you refreshing? I have a hard time imagining a rate-limiter blocking you unless you are refreshing at least a few times per minute for a prolonged period. OTOH I suppose it could add up if you are doing many pages, even once a minute or so. Curious about the details here.
They could be using automated DOS detection. Too many hits from the same IP in a given amount of time and you're blocked. The threshold would be set someplace along with the policy (blocked for x amount of time, blocked forever etc.). I would bet there is no human intervention except for updating the policy and that could be automated also.