We invested in an automatic door opener and closer
its FAB
It was ok during the winter when it didn't get light until 7 but as dawn has got earlier and earlier, and dusk later and later the auto door closer has been a lifesaver.
The coop opens just after first light, but the hens are still in the run - I then go and top up their food but leave them in the run until about 8.30 - gives the dogs a chance to have their breakfast in peace!
After they have had free range of the field all day I get them back in the run at about 5pm, then the door closer does the business at dusk (dark dusk) - I make sure all hens are in but to date they have taken themselves inside the coop about 25 mins before the door shuts.
You can adjust the sensitivity of the light sensor to open/shut earlier or later if needed.