Officially, who will comprise the cast of "New Amsterdam" beyond its current, fourth season hasn't yet been detailed, so whether or not Tyler Labine will appear in future seasons of the series has yet to be confirmed. That said, perhaps the most revealing piece of evidence indicating that Labine is here to stay is the fact that his list of upcoming credits on IMDb includes only one movie, titled "Killing Winston Jones," the filming of which is already complete. Labine, then, appears to be entirely free to appear in new episodes of "New Amsterdam," whereas if he recently learned his departure was imminent, his commitment to a new project would be all the more likely.
Furthermore, as recently as March 2020, Labine shared in an interview numerous reasons he enjoys portraying and even feels personally connected to Iggy as a character (via Daily Actor). Presuming that nothing has changed on his end, he's likely to want to continue his "New Amsterdam" tenure for as long as possible.
Finally, plans for a "New Amsterdam" Season 5 were announced prior even to the premiere of its third (via Variety), so barring a reason on Labine's end for leaving the series, it's likely his Season 4 contract also extends to the upcoming Season 5, given their concurrent announcement.
Iggy's resignation, then, may well change upon the premiere of the next episode of "New Amsterdam" on November 9.
