They publish every day digitally.  There are only 3 print editions each week.  This seems to be the way that papers are moving since print advertising is going by the wayside.  Instead of subscribing to a print copy, you subscribe to a digital edition.  You can still get a web edition free at
www.post-gazette.com. ; The web edition does not have as much detail on sports like box scores etc that the full-blown subscription does.