I wonder if RHP Alexander Vallecillo has gone the route of a few other Brewers' minor leaguers who essentially fade from the system with no formal transaction note (e.g. released, retired). He last pitched September 5, 2023 and isn't showing on any injured list to my knowledge.
In recent years, RHP Justin Bullock, RHP Ray Black, RHP Jose Chavez and OF Jose Gonzalez (DSL-level) similarly disappeared from rosters without a note, although the club later back-dated a transaction release post for Chavez (September 25, 2023).
Accounting for recent activity (and excluding Vallecillo), I note the organization as having 148 stateside players on minor league contracts who are not on 60-day or full season injured lists. I think that's a relatively healthy margin below the 165-MILB player cap, to be largely filled from the July draft and a few non-drafted player signings.