Asymptotic unit bar visibility number conjecture for complete bipartite graphs

Let $K_{m,n}$ be the complete bipartite graph with $m\ge n\ge 2$, and let $ub(G)$ denote the unit bar visibility number of a graph $G$. Asymptotic unit bar visibility conjecture. For $m\ge n\ge 2$,

$$ub(K_{m,n})=\frac m4+o(m).$$

This conjecture asserts that the known upper bound for the unit bar visibility number of complete bipartite graphs is asymptotically sharp.