A casing mill including a first milling configuration having a first blade for milling a first casing section, and a second milling configuration having a second blade, the second blade being an ultra-high expansion blade for milling a second casing section. A wellbore system including a borehole in a subsurface formation, two nested casings disposed within the borehole, a string disposed within the casings, a casing mill disposed within or as a part of the string and including a first milling configuration having a first blade for milling a first casing section, and a second milling configuration having a second blade, the second blade being an ultra-high expansion blade for milling a second casing section, the second casing section being radially outwardly disposed of the first casing section, and a stroking tool disposed between the first milling configuration and the second milling configuration.