Now that he has been activated, though, Bowman can begin on-field workouts. It does not necessarily mean he will practice or play right away, of course. There is no guarantee as to when Bowman will hit the field despite the 49ers originally projecting him back mid-season.
Bowman acknowledged he might not play this season, per the San Francisco Chronicle. The linebacker also doesn't know when he'll begin practicing.
If anything, the 49ers get the insurance of having one of their best defensive players on the roster in case a shocking turn of events occurs and they make the playoffs.