What's the date, in Usenet time?
Python 3, 109 bytes



from datetime import*
i=input()
z=date(*map(int,i.split())).toordinal()-727806
print([i,'1993 09 %d'%z][z&gt;9])


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-59 bytes thanks to notjagan
-3 bytes thanks to Mr. Xcoder
-2 bytes thanks to officialaimm
-12 bytes thanks to Jonathan Allan