Flying back from our visit to Phoenix on United and we stopped in before our 7 am flight. We were pleasantly surprised to find the club opened at 4am. We arrived around 5:30 and there was plenty of room. By the time we left at 6:15 the lounge was packed. Prior reviews noted that the lounge is small but the food offerings were pretty good. Oatmeal, yogurt, fresh fruit and bagels were all available and fresh. Plenty of coffee and juice as well. Could be tough to find a spot during the day. Maybe time to expand a bit?
Also, the ladies room has one stall ( so I'm told) and it was a bit crowded when the need arose.