I would recommend investigating the reasons behind the deactivation of the custom policy first. In this case, enabling / disabling the policy should be limited to certain users only. Verifying the Virtual DataPort logs located in <DENODO_HOME>/logs/vdp will assist in finding such information or any possible errors.
Take note that Denodo evaluates the developed policies based on certain [rules](https://community.denodo.com/docs/html/browse/latest/en/vdp/developer/custom_policies/custom_policies#:~:text=When%20a%20user%20queries%20a%20view%20and%20this%20user%20has%20custom%20view%20policies%20assigned%20over%20this%20view%2C%20the%20policies%20are%20evaluated%20in%20the%20following%20way%3A). Implementing the Custom policy as an option/restriction in a [global security policy](https://community.denodo.com/docs/html/browse/8.0/en/vdp/administration/global_security_policies/global_security_policies#:~:text=Custom%20view%20policy.%20A%20custom%20view%20policy%20is%20executed.%20The%20section%20Custom%20Policies%20of%20the%20Developer%20Guide%20explains%20what%20they%20are%20and%20how%20to%20develop%20them.) is a recommended approach since it can be easily applied and managed.
As for automating notifications , you could make use of the [Handler](https://community.denodo.com/docs/html/browse/8.0/en/scheduler/administration/creating_and_scheduling_jobs/configuring_new_jobs/handler_section) feature in Denodo Scheduler component. However, you would need to configure a relevant timely-based job that would test the queries relevant to your custom policy or invoke a stored procedure such as [GET_CATALOG_EFFECTIVE_PERMISSIONS](https://community.denodo.com/docs/html/browse/8.0/en/vdp/vql/stored_procedures/predefined_stored_procedures/get_catalog_effective_permissions) to gather relevant information.
For more information check out the following references:
[Custom View Policies](https://community.denodo.com/docs/html/browse/latest/en/vdp/developer/custom_policies/custom_policies)
[How to debug Denodo custom extensions with Eclipse](https://community.denodo.com/kb/view/document/How to debug Denodo custom extensions with Eclipse?category=Custom+Elements)
Hope this helps !