Strict Sign-off Mode (under Entities within Admin Settings) provides you with 3 options related to restricting sign-offs. You can enable all, none, or a combination of the below options:
- Restrict checklist and reconciliation sign-offs to assignees, managers, and admins only
- Make it so the same user cannot sign off as the preparer and reviewer on a single item
- Require preparers to sign-off before reviewers