@Anonymous
Once an instance of a Flow starts to run, it will run for a maximum of 30 days.
Each time the recurrence trigger fires, it starts a new instance of the Flow. That instance can run for a maximum of 30 days. The next time the recurrence trigger fires (daily, weekly, etc . per your configuration), that instance can run for 30 days.
The maximum recurrence interval for a recurrence trigger 500 days - in other words you can configure the trigger to run at intervals that you specify up to once every 500 days.
Here is a link to the documentation.