At which stage of enlightenment are the aggregates seen as not-self fully?

Question

In the Khemaka Sutta (https://suttacentral.net/sn22.89/en/sujato) Khemaka is an Anagami and he sees the aggregates as not-self. Based on this I guess the answer to my question is probably stream-entry or anagami, but I'm not sure.

This is a quote from that sutta:

“In the same way, reverends, I don’t say ‘I am’ with reference to form, or apart from form. I don’t say ‘I am’ with reference to feeling … perception … choices … consciousness, or apart from consciousness. For when it comes to the five grasping aggregates I’m not rid of the conceit ‘I am’. But I don’t regard anything as ‘I am this’.

Although a noble disciple has given up the five lower fetters, they still have a lingering residue of the conceit ‘I am’, the desire ‘I am’, and the underlying tendency ‘I am’ which has not been eradicated.

Answer 1

The conceit ‘I am’ is the 8th fetter; only fully eradicated by an Arahant.

Bhikkhus, there are these five higher fetters. What five? Lust for form, lust for the formless, conceit, restlessness, ignorance. SN 45.180

The stream-enterer has overcome 'identity view' ('sakkaya-ditthi'); which means seeing the group (body; kaya) of aggregates are not a self. However, the stream-enterer's seeing of the aggregates as not-self is obviously not complete enough to remove all ten fetters and uproot all outflows of defilements & conceit.

Therefore, arahant is the stage of enlightenment where the aggregates are seen as not-self fully.

Answer 2

Sakkaya Dithi (self-view) is fully eliminated in the Sotapanna (stream-enterer) stage.

Answer 3

At each stage of awakening, good householder, but only on the last, highest stage one would no more take on them again, even not in refined spheres.

Of course it can be that one isn't aware of the group-definition of aggregates, so the are also other sets of definition of the world. Worldlings do therefore, as long as not winned the stream, hardly understand Sakkāyadiṭṭhi.

[Note that this isn't given for stacks, exchange, other world-binding trades but to escape from the world of suffering]