  We show that within a $C^1$-neighbourhood $\mathcal{U}$ of the set of volume
preserving Anosov diffeomorphisms on the three-torus $\mathbb{T}^3$ which are
strongly partially hyperbolic with expanding center, any
$f\in\mathcal{U}\cap\operatorname{Diff}^2(\mathbb{T}^3)$ satisfies the
dichotomy: either the strong stable and unstable bundles $E^s$ and $E^u$ of $f$
are jointly integrable, or any fully supported $u$-Gibbs measure of $f$ is SRB.
