Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
It was six months for iPhone 13 models to start showing up:


However, as noted:
Since they’re not on there yet… I’d say at least a year? ¯\_(ツ)_/¯

I am err was hoping to wait for refurbished iPhone 15 Pro models, but the seemingly long(er) delay on Apple to amass enough refurb stock to post them for sale makes that a tough decision.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.