To recreate: 1 - set UpdateItemLocationOnCheckin to "_ALL_: _PERM_" 2 - have an item where items.permanent_location is null but items.location is not null 3 - check your item in, get message that location was updated, including wording "New value: "Blank"" 4 - check your item in the database, confirm location has been set to NULL rather than blank Getting location to have a value with permanent_location is null takes some niche setup to accomplish in the staff interface. See this comment for instructions, but it'd be easier to just set up a test item from the database: https://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=33301#c2 The UpdateItemLocationOnCheckin syspref contains the option to set things to "_BLANK_" at checkin. When that option is used, things are actually set to blank (items.location='') rather than NULL, so in those cases the message *is* accurate.