>Has forever ever been scratched out before?
yes it has. if the stamp doesn't sell the same year it was printed the forever value is removed and its value is fixed to whatever that days postage value is.
the only reason i know this is from a misguided adventure of buying 'forever stamps' online at a discount. sadly they all came with the forever scratched out and were little more than a trinket for a stamp collector.
its weird, i know. and kind of creepy. how the hell would the post office tell what year it was printed anyways? i know they use UV ink to determine postage authenticity but… the year?