Can metta be a gentle way into not-self, or does it quietly keep a sender in place?
In the early discourses, the Buddha points to the aggregates as a useful map: body, feelings, perceptions, formations, consciousness arise and pass, and the habit of claiming them as mine is where the clinging gets its grip.
One reading says metta needs a stable “I” sending kindness, so it may reinforce a conventional person. Another says the very warmth of metta loosens ownership, making the claiming reflex less loud and less needed, while the conventional person remains enough for speech, care and practice.
I am curious which way your practice leans. When you offer loving-kindness, do you notice a sender becoming more solid, more faint, or more unnecessary? I would value replies that draw on the suttas, on long sitting, on daily life, or on the historical context of the Buddha's teaching.
There is no need to solve it all; we are only asking where the practice goes when kindness meets inquiry.