At our HS, at least, the Naviance application counts per school do seem to reflect transcript requests.
For the school where my kid is applying ED, which typically has 20-30 applicants per year, the numbers blew up across September and mid-October and have since trickled up by a just a few, stopping at 27 applications. Because of when the volume shot up (weeks before the Nov. 1 ED deadline), it’s clearly not related to actual application submission.The transcript deadline for all schools a kid plans to apply to is tied to when their first application is due. I don’t know a single kid not applying EA or ED somewhere, so this should account for the vast majority of intended applications.
Looking at all of the schools where my kid is applying, at least, the volume seems largely unchanged from last year. Same with a few other popular schools at our HS (on average—one popular school seems significantly down, while another seems significantly up).
I’m sure they make exceptions and allow kids to submit one-off transcript requests past the deadline, especially after ED/EA decisions come out, so we might see another little bump in mid-December, in the few days before winter break. But I suspect 90% of the final volume is already accounted for.