This question came up in the Online 10-day Retreat Nov 3, 2020, guided by Delson Armstrong. Day 6 was part of a daily 30-minute discussion on the suttas, the Dhamma talk and reflections.
Slightly edited to improve readability
No, they cannot. If a meditator becomes a sotāpanna, a stream-enterer without fruition, at the dissolution of the body, at death, they will attain fruition of sotāpanna at that point in time. Their attainment, once they become a stream-enterer, is basically set, It’s not like they can go back. At the point of death they will have fruition and the lower realms will no longer be open for them.
With fruition it becomes solidified. The doubt goes away completely; there’s no more identity view, where there’s a sense of permanent self in anything; and of course, the belief in rites and rituals gets completely eradicated. Even at the point of stream entry, the entry into the Path, those fetters are destroyed. The fruition basically just solidifies it.
I want to give one little caveat here. The paths and the fruitions are not always so clearly defined in the suttas. There is mention of the other levels of Sakadāgāmi and Anāgāmi, and there might be some places where they do talk about Path and Fruition, but they are not so clearly defined.
Having said that, once you become a stream-enterer and you pass away without attaining anything further, at the level of death, you will still have the fruition and you won’t have any more that potential of entering any of the lower realms below the human realm.
