In the Mid-Acts community there is more than one opinion about that. But it is certain that it didn't begin at Acts 2. Then the Lord was still dealing with the nation of Israel.
There are basically two views on that within Mid-Acts...
Acts 9, and Acts 13.
Those two views is how the Mid-Acts label came to be, to begin with.
And the Acts 13 view was proven faulty long, long ago, but to those who learned the Acts 13 position long ago, and continued in it unexamined - to where the view became hardened in them - as often happens with the passing of time together with a thing left un-re-examined from scratch, from time to time.
Over the years, it results in one ending up so "dull of hearing" that they end up no longer able to be reasoned with.
Stam ended up that way.
Baker less so.
O'Hair ever remained open to re-examining his views.
And then you have one or two later, fringe views here and there - due to an incompetence in overall study approach simply because the individual had long ago set off on their own a bit too soon in their learning curve.
Men like E.C. Moore and his followers, come to mind.
In fact, much of the bickering back and forth between various individuals both within Christendom and on here - of all sorts of persuasions - is the result of those kinds of incompetencies and or hardening of the eyes and ears of one's understanding.
The result being that to point out a thing to such is often the same in result as never having pointed it out at all, to begin with.
You are not alone in that, but you...are a prime example.
I remain fascinated by these kinds of issues in perception; so thank you for your part in my continued edification on it.