The announcement you linked to doesn't seem to have anything to do with use limits.
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While we allow API users to have access to a lot of data through the API, it has always been against our API Terms of Use for third parties to use audio, audiovisual, images or artwork. In some instances, some data may have been indirectly accessible through a small number of API calls, and so as part of the recent API clean-up, we have corrected that anomaly.
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