The Blacklist's future confirmed by NBC after season 8
"He always played a pivotal role in the mythology of the show. At the time of his passing, we were in the midst of a series of episodes, toward the end of season 7, where his central role was coming to a head, where his knowledge of Red's truths were going to be sort of the engine of the whole story. "Because of that, we felt that we couldn't pivot away from his character, even after he passed, and do a different story, because we had not just told the story for the end of last year around him, but it had been the culmination of that year."
Source: digitalspy.com