Strong Butler conjecture on stability of dual spans

Let $C$ be a general curve of genus $g\ge3$. Let $(E,V)$ be a general generated coherent system in $G_0(m,d,n+m)$, and let $D_V(E)$ denote its dual span bundle.

Strong Butler conjecture. The bundle $D_V(E)$ is stable.

This is a strengthening of Butler’s conjecture. The source says that it is known when $m=1$ and $V=H^0(E)$ on a Petri curve, while the general case remains open.