Unfortunately, as of now, Planner in Microsoft Teams only sends notifications when a task is marked as complete or when someone assigns you a new task. There's no built-in way to get notifications for status changes like when a task moves from "To Do" to "In Progress."
Alternative Solutions
While there isn't a direct solution within Planner, you can consider these alternatives:
Stay up to date on forum activity by subscribing. You can also customize your in-app and email Notification settings across all subscriptions.
André Arnaud de Cal... 291,280 Super User 2024 Season 2
Martin Dráb 230,235 Most Valuable Professional
nmaenpaa 101,156