A homotopy exact sequence for overconvergent isocrystals

In this article we prove exactness of the homotopy sequence overconvergent $p$-adic fundamental groups for a smooth and projective morphism in characteristic $p$. We do so by first proving corresponding result rigid analytic varieties $0$, following dos Santos algebraic case. $p$, then proceed series reductions to case liftable family curves, where can apply result.