Schofield's completion conjecture for universal bundles on quiver moduli

Let $Q$, ${\mathbf{d}}$, and $\theta$ satisfy the assumptions of the theorem on partial tilting bundles, and let $\mathcal{U}$ be the universal representation on $\operatorname{M}^{\theta\mhyphen\mathrm{st}}(Q,{\mathbf{d}})$. The bundle $\mathcal{U}$ is a partial tilting bundle, meaning that it is a vector bundle with $\operatorname{Ext}^{\geq 1}(\mathcal{U},\mathcal{U})=0$, though it need not classically generate the bounded derived category. Schofield's completion conjecture. The partial tilting bundle $\mathcal{U}$ can be completed to a tilting bundle. This conjecture is attributed to Schofield and is presented as the second part of a conjecture on tilting bundles on quiver moduli; the paper proves only the partial-tilting assertion, so the completion remains unresolved here.