  Using discrete flavour group, $A_5$, combined with generalised CP, we study
the mixing parameter correlations which arise from breaking to residual
symmetries in the neutrino, $G_{\nu}=\mathbb{Z}_2\times \text{CP}$, and charged
lepton sectors, $G_{e}=\mathbb{Z}_2$. By focusing on patterns that agree with
current experimental data we demonstrate that non-trivial leptonic phases are
predicted and discuss a number of distinctive correlations between mixing
parameters.
