Last time we went we didn't get to see it all, that was last week of august as well and it wasn't too bad. But we are going on a Saturday this time. We are going to De Eemhof centerparcs for a week first then have booked a hotel nearby Efteling for the Friday and Saturday. Apparently it's open until midnight on Saturdays in the summer. I suspect it will be busy and we will be exhausted, but it's so lovely I want to go again while DCs still want to go with us.