One problem that athiests run into with time is that not only does it not flow evenly, but apparantly had a clear beginning with the big bang. Theists love that and say that the universe had a beginning. But what seems to be very great about this idea is that it is perpetual. The 2nd Law says that disorder is always increasing. It never says anything about starting to increase.
Disorder is independant of time.
So prior to the big bang, disorder was increasing. But perhaps that is mute. Yes, real time existed before Big Bang. Universe mathematically comes from basic symmetries.