Are you sure you tested what happens when you reach the end of the playlist by playing? Reaching the end by skipping is different.

I hit Next to reach the last song, then fast-forwarded to very near the end of the song and then allowed it to come to the end. I did not play the entire playlist without fast-forwarding.

One possible difference is that all my playlists are tagged as "Automatically repeat", so I had to manually deactivate the "repeat" feature before performing the test.