For us living in KY right on the border of CST and EST it doesn’t get dark until close to 8:30 or 9:00. My DH doesn’t get home until after 6:00. We all work in the garden and do all the farm chores too. So we don’t get the kids to bed until 9:00 or 9:30 by the time we do baths, family devotions, and read alouds.
So are summer bedtime schedule is much different then our rest of the year schedule. That means the dc normally wake up later in the morning too..instead of 7:00 it’s more like 8:00 and sometimes 8:30. And even my oldest take “naps” sometimes during the HOT afternoons if they need them.
No matter what time of the year or what time they wake up we do the same routine of work. I don’t hold firm to the exact time but just the routine of chores and work.
To answer your question…I think “reasonable” is relative to your family. Some people would think I am horrible to let my kids all under the age of 8 stay up until after 9:00 sometimes 10 but it works for our family.
HTH,
Shelly