The asphericity conjecture for arrangements of ideal type

Let $\Phi$ be a reduced root system with Weyl arrangement $\mathscr A(\Phi)$. An arrangement of ideal type $\mathscr A_{\mathcal I}$ is a subarrangement of $\mathscr A(\Phi)$ determined by an ideal $\mathcal I$ in the positive roots of $\Phi$. Asphericity conjecture. Any subarrangement of ideal type $\mathscr A_{\mathcal I}$ of $\mathscr A(\Phi)$ is a $K(\pi,1)$-arrangement. The preceding results prove the claim for all classical root systems and for many arrangements in exceptional types, leaving only the listed exceptional cases unresolved.