I don't think on-park announcements or advertising will work all that much. I agree that using the screens around park to make it clear what time the park closes is not a bad thing. But if people are oblivious to the closing time, think it's 6pm (say), and then rock up and find out at 2pm it's actually 9pm, I don't think that will encourage that many people to stay. I think there's two things to keep in mind with later opening hours. You need to give people a reason to stay. Fright Nights is always packed until close, because there's a reason to stay (scare stuff and night rides). Summer Lates had a DJ and maybe one night ride if you join a queue late on. For many, that's not enough to get people to stay. You have to accept that people will leave early. At similar sized parks (and bigger), people leave before park close, especially when there's late closing. Just as a recent example: I went to Dollywood last month, 10am-9.30pm opening hours. All day, Lightning Rod had 45min+ queue, except in the last hour where it dropped to 5mins. People leave early. And that's fine, so long as you're busy enough during the day and people who stay late get their money's worth. I was on park both Fridays and staying late felt worthwhile. If it translated into people spending money and giving better KPI scores it's worth it. The park just need to come up with a way of making staying later more appealing, and advertising that a bit more.