I appreciate the answer. And I understand that you may not have more-granular info than this.
But I am wondering what how jobs were advertised prior to utilizing ProbOff/CL. Maybe the answer is this. There was no avenue to get job listings in front of the most likely eyeballs.
Bit of an aside, but if anyone else is in this position and trying to reach the eyeballs of jobseekers who aren't actively using portals, I really can't recommend local Facebook groups enough.
A post from a real account (not the business) saying "Gizmo Plastics are hiring line workers for $18/h, anyone interested?" will get some guaranteed traction. In my small town Ontario groups, I've never seen a post looking for laborers go ignored.
Outside of an urban area, you won't necessary be overwhelmed with resumes. If you portray your job realistically, you'll get people realistically interested in your job.
Son #1 got employed there early but it turned out that a small group had a deal with management and got 100% of the work. New hires went out on one job immediately and then never again.