What about one who intends disbelief at the time of death because he will no longer be held accountable?

Whoever intends disbelief in the future disbelieves immediately, because the resolve to disbelieve is disbelief. So, whoever intends disbelief at the time of death is a disbeliever. A Muslim's deeds are judged by their endings, and what a Muslim most desires is a good ending. Whoever disbelieves at the time of their death has ended in apostasy, and they will abide eternally in Hellfire, due to the Almighty's saying: "Nor those who die while they are disbelievers. For those We have prepared a painful punishment."