Not necessarily. I waited longer for the Little Mermaid AP preview than I did a few days later when the ride opened. But it was obvious the ride was having issues as they cleared the queue when it stopped and we're closed for 30-40 minutes. Then it stopped for several minutes when I finally did get to ride. They may not be running the ride at full capacity for a preview. Generally if I'm only planning to go for a special event I just figure I'm investing the extra time for that event. Then anything else like riding other rides or seeing a show is a bonus.
I don't remember how long exactly, I think it was more than a 2 day preview, though. After waiting 30 minutes for the ride to come back up we had to wait in a line to have our APs scanned (have done other previews where this took a minute with only a few people, but this time it was a long line) and then the line extended all the way down to the end with the switchbacks and most of the queue used. It might have been 20 minutes, not sure, it felt longer. When I went back the day after it opened there was briefly a long line that extended to Golden Zephyr, but moved much quicker. They gave FP to on site hotel guests, so that slowed it a little. Then I went back 2-3 days later, so the ride had been open 5 days, and walked right into the building. I expect Peter Pan to be more like Alice, which I don't think had an AP preview. The line was consistently 45 minutes for a good month, which is only 5-10 minutes longer than usual, but about the maximum amount of time people want to be squished into that little space. With Peter Pan typically running 40-60 minute waits I can't imagine most people putting themselves through more than 75 minutes of that line, 90 the first few days. But I think there are enough APs willing to wait an hour that you'll see it at least that long in the morning and after work hours. It can be kind of hard to predict what exactly people will come out early and line up for and what the capacity of an event will be. I remember the Baymax preview filled up very quickly during the AP preview but PFF wristbands stayed available all day.
