This paper discusses the influence upon a smectic C liquid crystal cell of backflow induced by the relaxation of alignment following the removal of a strong electric or magnetic field. Our study, based upon a recently proposed continuum theory, concentrates upon the homeotropic configuration in which the smectic layers are parallel to the boundary plates, but some consideration is also given to the bookshelf geometry. Although the governing equations prove to be rather complex, some progress is possible analytically by repeating an approximation made in the corresponding problem for a nematic.