Subaru Transmission

The automatic transmission in my 1999 legacy sedan (90K miles) will downshift at odd times, e.g., when it is coasting downhill. What could be causing this? should I be concerned? Haven’t taken it for diagnosis yet.

My 1999 Outback has a downhill downshift feature to control speed and use the engine as resistance in addition to the brakes, much like downshifting a manual transmition.