Depends on the property.
One of the properties I hunt, the summer bucks stay through fall. On most other properties half leave and new ones show up. So on the property where they stay, I start putting out cameras in late July to get an inventory of what bucks are using the property. On the other properties where the bucks disperse, I wait til late September early October to put them out.
Late July is usually when you start seeing a buck's true potential since their antlers will be almost done growing. Most bucks will be done growing antlers by early August and the hardening process starts about mid August.