Whoops! Hopefully, I fixed the video link. It should work now.
And yes, you're 100% right..."I think a policy that says "Doors remain locked until 7:30am." or "Entry is permitted after 7:30am" is not governing people but property." That is a great way of doing it.
Remember, how policies are phrased is extremely important. The letter of the law is just as the spirit. So, even though saying "No one may start working before 7:30am" may seem very similar to, "Doors remain locked until 7:30am" one would be invalid and other valid, even if they have the same intent.
By hours of operation, I was addressing how organizations typically try to regulate them, which is through things like "Everyone must arrive by their scheduled time" or something like that.