According to Gruber's sources, Apple filed a bug on the iPhone 4 antenna issues two whole years ago.
We already know that Apple employee Ruben Caballero, focused on antenna design at the company, raised the issue of signal loss last year. But according to Gruber's recent blog post, they might have known even before that, so "there was plenty of time to find a solution to the problem."
In fact, two years ago Papermaster joined Apple—in November 2008, when he joined from IBM to head up the iPod and iPhone engineering team as their Senior Vice President of Devices Hardware Engineering.
Speculating that things turned sour long before he was given the boot last week (or, to take a stab at Apple's official line, left of his own accord), the Wall Street Journal has this interesting bit to say about Papermaster:
"Mr. Papermaster had lost the confidence of Mr. Jobs months ago and hasn't been part of the decision-making process for some time, these people said."
Plus, the fact that he didn't appear on stage at the iPhone 4 free bumper keynote, nor in the iPhone 4 video from several months back, does lend certain credence to the notion that things have not been rosy between Papermaster and Apple for some time now—considering Bob Mansfield, Head of Mac Hardware Engineering, made the appearance himself, despite Papermaster being the lead exec of that unit and better equipped to talk about the iPhone 4 engineering process. [Daring Fireball and WSJ]