If the number of agents and volume of calls has increased in those queues, that could cause them to take longer to run. Also remember, historical report is running on the actual server, so if call volume is high, you're taking away from the server, would could cause the reports to run longer. If you are running the report daily for the previous 24 hours, try scheduling the report to run at your slow time of day (3am for example). That will put less stress on your server, plus it will be waiting for you when you come in in the morning.
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