The purpose of this paper is to extend the results of [4] in order to achieve more versatile, convenient stability criteria for a wide class of finite-difference approximations to initial-boundary value problems associated with the hyperbolic system ${{\mathbf {u}}_t} = A{{\mathbf {u}}_x} + B{\mathbf {u}} + {\mathbf {f}}$ in the quarter plane $x \geqslant 0$, $t \geqslant 0$. With these criteria, stability is easily established for a large number of examples, where many of the cases studied in the recent literature are included and generalized.