Let “grurple” mean green before a designated “zero hour and purple thereafter. Let “emerow” mean something that is an emerald before the zero hour and a cow thereafter. Then the green emerald confirms “All emerows are grurple,” which is to say, the green emerald will be a purple cow in 2014. By suitable choice of terms and zero hour, anything confirms that it will be anything else at any later time.
Sometimes philosophy can appear slightly weird but I think its natural. Weirdness is a necessary part of philosophy. It’s a fundamental quality philosophers need to work with in examining the limits of thought experiments.