Board Thread:Theories and Speculation/@comment-44437908-20200507033747/@comment-6769189-20200508102200

I dont think it matters if they die at the same time... nothing states they have to die at the same time or both be dead at the same time to reincarnate and nothing says they had to reincarnate at the time of their deaths.

Madara did die at the Valley of the End. His resurrection wouldnt undue the transmigration process. We know this because we saw him resurrected but it didnt interfere with Sasuke's status as a transmigrant.