Are you talking about email subscription. add another dashboard in subscription and delete old task.
I am in a similar situation like Gaurav.
I am using tableau server Version: 10.4.0.
My scenario is to have a daily subscription and from the email received to trigger a report on tableau server (not the report that generated the subscription).
The report that generate the subscription already have the needed URL action in place and it's working as expected on tableau server. But once I received the email subscription and I click on the URL action it is opening the report behind the subscription...