A Planner Webhook that delivers change notifications will open up tremendous opportunities to integrate Planner Tasks with many existing and new applications and workflows to the benefit millions of users.
This essential API feature is already available for Todo Tasks, SharePoint Lists, Outlook and Teams.
This request already has over 100 developer votes in the soon to be deprecated Planner User Voice and has been an outstanding since 2016
When will a Planner Webhook be available? See the latest answer here
Can we please get an ETA?