Interesting.
Doesn't make sense nowadays, when everyone gets their news in real time.
It's also confusing for future researchers. For example, if you want to read about 9-11, you wouldn't see anything about it in the September 15 issue of news magazines, four days after the event happened. You'd have to look for the Sept 22 or 29 issue, long after the news actually occurred.
I found that particular cover. It was undated. May have been a special issue. It's been a long time since I've researched magazine contents. Long as in it was on microfilm! IIRC, records show the published date, not the cover date.