With the recent report of energy and angle interferences in below-threshold photoexcitation Auger process due to the post-collision interactions [Phys. Rev. A 98, 013421 (2018)], similar interferences are also found in double continuum wave packets from a two-step time-delayed photoionization of a two-electron atom. Properties of the interferences are studied in detail with respect to laser pulse time widths, laser frequency chirping, and ionization time delay. The effects of these physical quantities on the resulting interferences are discussed.