We discuss the role of time-dependent observables in probing CP-violation in b --> s l+ l- and b --> s nu nubar decays. We identify a set of new observables by looking at the time evolution of the differential decay rate of B_d,s --> P(S) l+ l- and B_{d,s} --> P(V) nu nubar where the interference of B_{d,s}-barB_{d,s} meson mixing and decay is probed. We show that these observables do not require a time-dependent analysis but could be obtained by time-integrated or time-asymmetries if flavour tagging is available.
These observables are precisely predicted in the SM, are unaffected by NP in models with real contributions to SM and chirally flipped operators, are independent of form factors and are unaffected by hadronic uncertainties. They are however sensitive probes of NP scenarios involving new CP-odd phases.