  Considering a doubly holographic model, we study the evolution of holographic
subregion complexity corresponding to deformations of bath state by a relevant
scalar operator, which corresponds to a renormalization group flow from the
AdS-Schwarzschild to the Kasner universe in the bulk. The subregion complexity
shows a discontinuous jump at Page time at a fixed perturbation, where the
discontinuity depends solely on the system's parameters. We show that the
amount of discontinuity decreases with the perturbation as well as with the
scaling dimension of the relevant scalar operator.
