I am a parole officer by training. All officers who work in penitentiaries will tell you, as I do, that the criteria for going from a maximum-security to a medium-security institution are easier to meet than those for going from a medium-security to a maximum-security institution. It's much more difficult in the latter case because the tools are more specific, more demanding, and there are more criteria that have to be met. That's what I would say.
So you mustn't think that, because you've gone from a maximum-security to medium-security institution, you'll necessarily be going from a medium-security to a maximum-security institution in a short period of time.