Scope

Do not send emails for cancel subscription email for scheduled cancellation. 

How to restrict email notifications for a scheduled cancellation subscriptions?

Solution 

This can be done using the Email Segmentation feature in Chargebee.
Navigate to Settings->Configure Chargebee-> Email notifications-> Click on Manage segment-> Create new filter->Select the filter as has scheduled changes as false from the subscriptions tab -> Save the filter so that only subscriptions without scheduled changes will get the Cancellation emails.

Here’s more information about Email Segmentation.