Comptuer simulation on a two-dimensional anisotropic lattice-gas model of oxygen ordering in high-Tc supeconductors of the YBa2Cu3O7- -type shows that the ordering dynamics obey algebraic growth laws which are different in the ortho-I and ortho-II phases. It is possible to relate this dynamical scaling behavior to a similar scaling in the experimentally observed temporal variation of the superconductivity transition temperature, hence suggesting a specific coupling between the coherence of oxygen order in the basal Cu-O planes and the superconducting state.