We study classical scattering phase of CP2 dyonic giant magnons in R-t x CP3. We construct two-soliton solutions explicitly by the dressing method. Using these solutions, we compute the classical time delays for the scattering of giant magnons, and compare them to boundstate S-matrix elements derived from the conjectured AdS(4)/CFT3 S-matrix by Ahn and Nepomechie in the strong coupling limit. Our result is consistent with the conjectured S-matrix. The dyonic solutions play an essential role in revealing the polarization dependence of scattering phase.