All of the unused GE Cards have punched "filing" holes as seen at the right of the card. This feature is absent on this card. In fact, this ad is on the back of an otherwise ordinary UX38 (S54) card. It has recently been proven (by their existence) that ordinary UX38 cards bearing GE ads were in use prior to the rate increase. This card may in fact have been retained as an advertising sample specimen card prior to the rate increase which gave birth to the GE surcharges.
It is interesting to note that this ad is present on the known counterfeit GE overprints. Perhaps those were once the sister sample cards to this one.