[Koha] Withdrawn items showing in OPAC search results (again?)

Hi all, I have a package version of 16.05.09 running on Ubuntu. I have my OpacHiddenItems system preference set to "withdrawn: [1]" which I'm quite sure used to successfully hide items with a "Withdrawn" status, but after a recent upgrade to 16.05.09 doesn't seem to hide them any longer. Anyone else running 16.05.09 now seeing withdrawn items or know why this might be happening? Thanks! Steve