a valve body having first and second ends, the first end being configured to removably affix to a plug component, the valve body defining an opening toward the first end and defining a port toward the second end, the valve body defining a passage extending between the port and the opening;

a piston being movable on the valve body from a first position to a second position, the piston defining a piston chamber;

a control valve disposed in communication between the wellbore and the piston chamber and being configured to capture wellbore pressure in the piston chamber as captured chamber pressure;

a closure disposed on the valve body and being configured to transition from a closed condition to an opened condition relative to the port in response to the movement of the piston, the closure in the closed condition preventing fluid communication through the port, the closure in the opened condition permitting fluid communication through the port; and

a fixture releasably holding the closure in the closed condition on the valve body, the fixture being configured to release in response an increased pressure differential on the piston above an initial pressure differential between the captured chamber pressure and the wellbore pressure.