The Linux package, 'sdate' will give you the current Eternal September date:
$ apt-get install sdate
#EternalSeptember #1993 #Usenet #NewsGroups #Linux #sdate #datetime #calendars
It has come to my attention that #sdate does not support SOURCE_DATE_EPOCH. I will have to carve out some time to write a patch, if someone else doesn't beat me to it.
Haha, mentioning Eternal September earlier today led me to discover #sdate, the unix-style program to output the current date based on the idea that September, 1993 still hasn't ended. http://www.df7cb.de/projects/sdate/
In case anyone is wondering, today is the 9,565th