Cells, holding cells and solitary cells must now be "Enclosed", which means surrounded by walls and doors.
There will be no more building tons of open cells in a giant indoor area without any walls seperating them.
What's the justification for this change? Personally I like creating super-dense open-plan prisons. I realize it's cheaper to have no interior walls, but I think it could eventually be balanced by the fact that an open prison needs to keep the prisoners happier to prevent epic riots. If PA is going to allow different play styles, why not this one?