Watchtower and Awake! two year cycle.
JW: Would you like a copy of our latest Watchtower magazine?
HOUSEHOLDER: (looking closer) Hang on. I already have a copy of that magazine. In fact I remember you giving me a copy two years ago.
JW: Well, yes, but this Watchtower magazine has 'new light' teachings which replace the 'old light' teachings in the Watchtower magazine of two years ago.
HOUSEHOLDER: What the f¥€#.