Merge Request System Hook does not Fire when Security Policy Approval updates to Optional

We have a System webhook that receives changes when a Merge Request event is published. We are noticing that if a security-policy approval rule applies to the Merge Request, it first applies as Required and then (if appropriate) changes to Optional after the scan as completed. However, when the security tooling changes the approval rule Optional, the Merge Request System Hook event is not published to indicate a change to the merge request.

Is this a known issue, or is there a different way to connect a hook to receive this type of event?