I'm sure 3-5 AM is the usual hour for people to start making breads to sell/breakfast.
for fresh baked goods, yes, because you need the dough to rest and rise. and that generally takes about a half-hour to an hour alone, then there's the baking time and volume of prep. the baker at the university I used to work at would show up at 5 am, and literally not stop baking till their shift ended at 3 pm. And that was just to cover till they came back the next morning.