Given I write with at least my 9 beats filled in - I generally know what I want to happen at the end of Act 1 - i.e. between p. 25-30. When I am intuitively writing my first draft, I'm looking to see that that beat is there and that I'm not wildly off with the story track. Still, there is room for changes, additions, etc. but generally I want to know what that beat is at the end of Act 1 and hit it. Even in that vomit first draft, I often do.

There has been a general shift in the last two decades or so: What used to be acceptable for an Act One end is now often the midpoint of Act One. Lots of possible reasons for this, but perhaps the most significant one: Moviegoers want stories to get up and go more quickly. So if your end of Act One is when your Protagonist decides to do something, reacting to the Something Happens / Call To Adventure, more than likely a script reader will ding your script for that. While you have to balance everything out in terms of introducing characters, establishing the Ordinary World, and so on, it's safe to say you're better off getting your Protagonist into the New World ASAP, and certainly by the end of Act One.