Siebe wrote: “-according the sutta’s the buddha did not teach an arahant does not exist anymore after death. He also did not teach he does exist, nor did he teach that he both exist and not-exist, nor did he take the stand of nor-existing nor not-existing.”
This is a deep point.
In an ultimate sense, it is not possible to say “a person exists” because all five aggregates keep changing (a man is not the same compared to when he was a baby, both mentally and physically).
On the other hand, it is not possible to say that man “does not exist”. Obviously there is a man who lives.
This is why the Buddha rejected both those extreme views. At every moment a living being (or any sankata) has an existence that is dictated by Paticca Samuppada.
Furthermore, there is a continuation of this Paticca Samuppada process after death for a normal human (because there are causes and conditions to sustain that process)
– However, an Arahant has stopped the CONDITIONS for that process to proceed to at the moment of death (cuti-patisandhi), even though there will still be causes (past kamma) left. Therefore, that rebirth process is stopped for an Arahant.