Structural, transport, magnetic, calorimetric, and neutron data were reported for the oxygen-annealed Pr1+xBa2-xCu3O7+y or 1212-type Cu(Ba2-xPrx)PrCu2O7+y system (0 less than or equal to x less than or equal to 1, -0.11 less than or equal to y less than o