I’m not the expert to answer this question, but I will give my opinion. To me, if a finder qualified for the cache at the time he or she logged it, it is a valid smiley. If not, then no. If the finder qualified previously, but the challenge needed to be updated for one reason or another, I would say the find is still good, as the qualifications were met at the time of the find.
I don’t do many challenge caches, but I liken this to, I make a find, but the cache goes missing some time later, and the owner has to make a replacement (maybe a tree got chopped down or a sign removed), and the owner has to relocate it a bit or place a new sized container. If it is the same cache page, just updated, my find remains valid. I am welcome to find the new replacement, but I don’t get another find out of it. Same with the challenge–the finders who had previously met the challenge requirements but now do not, would be welcome to update the cache page with a write note entry stating such, but would not be given another find, nor would the previous smiley be removed as stated above. I hope my thoughts aren’t too confusing.
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