Archive escalation policy
Guide to archiving escalation policies on Spike.sh
You can choose to archive an escalation policy given that the policy is not associated with any existing integration.

Select archive under settings
If your escalation policy is already in use on other integrations then you won't be able to archive. Edit your integrations to associate with another escalation.
Once the escalation is not in use with any integration, you would be allowed to archive.
No
No. In fact, the existing incidents will prompt you about archived policy to avoid misinformation

archived policy in existing incident
There is no automated process. If you certain about restoring talk to us via chat from the dashboard or email us at [email protected]