I believe pre NAFTA Mexican avocados were not allowed imported. Or it was a tight quota. I don’t recall exactly but it was a political issue. CA avocado growers had a lot of power.
The Mexican fruit was not allowed in until relatively recently -- except for certain times of year. That prohibition protected American growers.
We can thank the Chilean imports for breaking that set-up. Or curse them under one's breath sort'a like the Morro growers would.
The deal there is that the Morro fruit would come in late, and so pretty consistently would fetch a good price.
The changes made harvest strategizing difficult. I do not pretend to know the answers. (not enough information on when other harvests are most likely to come in, critical price points, etc.)