What is the difference in early bird hours is this open to everyone

Yep. If they open early all personnel with a active duty, dependent or retired ID can go and use the Commisary. They are mostly open for people to grab small amounts of stuff but I have shopped early and bought normal amounts for grocery shopping and they didnt seem to mind. Hope this helps

Also, if you check-out before the normal opening time, there is a limit to items you can buy. I think it is 20 or 25. When I would go early, I would shop until the normal opening time and check-out with no limit on items.