There's going to be a lot of Fire Emblem to go around the table after Three Houses launches this year. So we know that Nintendo is releasing DLC that will run through April 2020, allowing for an already long tail. But thanks to a tweet from Nintendo of Europe, we also know that the publisher plans on giving us at least one free update.
According to the tweet, there will be a free DLC update later this year for something "beyond normal and hard mode," that adds "an even harder" difficulty setting to the game. This mode isn't named in the tweet, but "difficult," "lunatic," and "maniac" have been monikers that have described more challenging settings in the past. Typically, these esoteric alterations allow for even more restrictions for players in addition to stat changes, like an increase in enemy counts and more skills for enemy elites.
As I mentioned in my review, I immediately started a second run of the game with a new house after finishing my first. I replay Fire Emblemgames frequently, so the more modes to accommodate longevity, the better.
Nintendo of Europe [Twitter]