I've heard of someone getting an invite 3 days before the U of T interview a couple years ago. But that was only one case and I heard it from a friend of a friend so not 100% sure if it was a true story.
Invite/Rejection: Invite
Time Stamp: 2:39 PM EST
Location: IP
Stream: English
wGPA: 3.99
Current year: 4th year
ECs: No research, pretty basic with athletics, volunteering, work, some scholarships
Casper: Got me a Mac interview with 127 CARS
Could be a trial run. Other universities have used Casper without factoring it in to admissions then see if the Casper scores correlate to achievement for that cohort in the coming years. If they find the students that did better on Casper are doing better in school or are performing better in social settings for example then they might decide to make it count for admissions.
Edit: Same idea for essays.