Peter (Joshua Jackson) will be missing from the early episodes of the sci-fi drama's fourth season, after being erased from history in last year's finale.
"Coming from a fan perspective, and also a marketing perspective, [Fox said], 'We need Peter back right away because people miss Peter and we need him back'," Pinkner told Give Me My Remote. "Our counterargument was, 'To really establish his absence will take a little while'."
He added: "[It will] truly [be] a little while, not a long while, because we know there is good audience frustration and really bad audience frustration."
Co-showrunner Wyman also suggested that permanently removing Peter from the series would be "insanity".
"He's such a huge part of the show and people should know that," he said. "He's just inextricably linked to the [show's] DNA. So that's one thing we couldn't believe people would think we were thinking of."
Fringe returns to Fox tomorrow night at 9/8c and will air in the UK from September 28 on Sky1.
> Fringe: Season four premiere in pictures
Watch Anna Torv discuss Fringe with Digital Spy below: