I think Theoarn must have been talking about the lions on the K. Safari Ride at AK park.
The animals are out most of the day (and night) except for when they take them in for 2 hours in the morning to check the animals, etc. They rotate each savanna. A couple years ago it was 6:30am for Uzima, 8:30 for sunset and 10:30 for Arusha. The best time to see the animals are when they are feeding them at various spots close to the lodge; the morning and early evening.