Brešar–Klavžar–Rall–Wash conjecture on subdivisions of subcubic graphs

For a graph $G$, its 1-subdivision is obtained by replacing every edge with a path of two edges. The packing chromatic number $\chi_p(G)$, or PCN, is the smallest positive integer $k$ such that $G$ has a packing $(1,2,\ldots,k)$-coloring. Brešar–Klavžar–Rall–Wash conjecture. The $1$-subdivision of every subcubic graph has PCN at most $5$. Many advances have been made toward this conjecture, but the supplied status evidence says that it remained open since 2016.