In [Fos16] Foscolo constructed a family of hyperkähler metrics on a $\K 3$ surface that collapses to the flat orbifold $\mathbb{T}^{3}/\mathbb{Z}_{2}$. The collapse has bounded curvature away from finitely many points, and is given by shrinking the fibers of an $S^{1}$-fibration. In the simplest case, curvature blow-up occurs at the 8 singular points of $\mathbb{T}^{3}/\mathbb{Z}_{2}$, where the bubbles are given by complete hyperkähler spaces with cubic volume growth, which in this case are ALF-$D_{2}$ spaces. See [CC15, Min11] for a partial classification of hyperkähler ALF spaces. Let us also point out that the results of [Fos16] have motivated the study of codimension-$1$ collapse of $G_{2}$-manifolds to $3$-dimensional Calabi-Yau manifolds in [FHN17].