Here's the exact quote
If a player doesn’t report to training camp at least 30 days before the start of free agency, he loses an accrued season toward free agency. In order for Donald to become an unrestricted free agent in 2019, he has to accrue at least four seasons. Currently, he’s at three.So they're saying he becomes unrestricted next year if and only if he reports 30 days before the season starts, not the start of free agency. He does have to get 4 seasons accrued to get to free agency. The Rams would simply franchise him if he gets there. Hope that helps.
RFS69