Regular update multiple records in CRM Online

Hi guys,

We have a client that requested from us to update case records on a daily basis. It is possible the amount of records to be in the hundreds of thousands. We were thinking to create a workflow which timeouts for 24 hours and updates a field in a custom entity which triggers a plugin which executes the update of the records using the ExecuteMultipleRequest. But CRM online restricts the plugin execution to 2 minutes and then the plugin timeouts. Is this possible to achieve using the extending functionalities of the CRM or we have to use some kind of third party tool?

Best regards,

Emil