Maintenance Mode | Heroku Dev CenterIf you need to temporarily disable access to your Heroku app (for example, to perform a large migration), you can enable Heroku’s built-in maintenance mode. While in maintenance mode, your app serves a static maintenance page to all visitors. While maintenance mode is active, the error code H80 is returned in your logs. Scheduler jobs can still run while your app is in maintenance mode. Be mindful
