OK, so here's the way it works. All 4 teams (AAA, AA, High A, and Low A) play against the minor leaguers of the same organization.
The Reds rotate against 4 teams (Orioles, Twins, Rays and BoSox) The AAA and AA teams will be at one teams location, and the other 2 teams will be at the other teams home site.
The prime days are when they are playing Orioles because the Orioles do minor league Spring Training in Sarasota also so you can watch 2 games simultaneously, then drive across town and watch the other 2 teams playing.
And personally, for me, full squad practices (for both major and minors) are the hidden gem of Spring Training. For the minors, you get to see all players all at one location, and you get to see them a lot rather than one or 2 at bats.