Since the emailHygiene service is an ever-evolving platform, updates depend on when upstream data partnerships provide data. Depending on the type of data, our updates in 15-minute, hourly, daily, monthly, and quarterly intervals. We verify against multiple data sources to ensure our data as high of quality as possible, which is why there is such a large gulf of update interval times.
Email verification is always done in real time and is not based on cached server data.