If you play a level for approximately 4.53 years (~1657 days), the timer value wraps around back to 0:00!

Also, if you play for over ~0.31 years (~116 days), the IGT displayed will have this value:

So there's a range of ~1541 days where you will always get this end time, and then after that you're back on 0:00.

The more you know!