If a jw places an old copy of a mag, do they need to ensure that their has not been some new light which replaces the teachings of the mag??
They really don't want you having many back issues laying around. If you keep being overstocked in your inventory, you are supposed to reduce your standing order. The problem with that is people see and hear you cut back your order and it can be embarrassing. That was my experience as a witness - and a former pioneer at that.
Regarding new light, we were counseled to not leave anything older than 6-12 months. Ideally, we shuld have no residual mags and just leave tracts where people are not home. Leaving old mags at not-at-homes is where most of my placements came from during my last several years as an active witness / publisher.
-Aude.