I speculate that Jotipala aka Gotama became a sotapanna under Buddha Kassapa. In MN 4, Gotama described himself prior to his right self-awakening as having "gone beyond uncertainty & doubting". This is a clue that he was a sotapanna because only a sotapanna could have eliminated this mental fetter. Also, in my opinion, if he had not caught a glimpse of nibbana that was etched firmly in his mind, it would be very difficult for him to be disenchanted with the teachings of Alara Kalama and Uddaka Ramaputta. Lastly, the lifespan of a deva is very, very, very long, that is, if you believe there are devas.