  We consider the possibility of a large phase of B_s-\bar B_s mixing in
supersymmetric SU(5) and SO(10) models. We find that in the SU(5) model, the
magnitude of this phase is correlated with the branching ratio of \tau ->
\mu\gamma and the phase can be within 2\sigma of the recent UTfit analysis. In
the case of SO(10) models, this correlation can be relaxed and a large phase
can be obtained. In this scenario, a non-zero value of CP asymmetry for B ->
X_s\gamma will be predicted. We predict the sparticle mass ranges for the LHC
for these models once the UTfit result is accommodated and discuss the dark
matter and the anomalous magnetic moment constraints on this analysis.
