Title says it, pretty much.
4 free score report per sitting.
Neither the SAT nor subject tests have 8 free score reports. For any test you take, you get 4 free reports as long as you designate the colleges in your test registration as ones to receive scores automatically upon release.
No there are actually four additional ones online.
What do you mean “four additional ones online”? My understanding has always been that you get four free sends with your test registration for any particular test date. You can only get an additional four free sends if you are entitled to a fee waiver, meaning typically that family income is below low income thresholds, and I did not perceive the OP was asking about fee waivers.
Yes, using a fee waiver, I can get four additional ones online. I’m asking whether the same policy applies to the SAT Subject Tests too.