Agreed. But we can put it in another way too.
When one attains the Sotapanna stage, one has removed the ten types of micca ditthi. He/she has also removed some of the micca ditthi associated with not comprehending Tilakkhana. Now one is on the Noble Path.
Furthermore, one becomes a Sotapanna Anugami when one has removed most of the ten types of micca ditthi, and HAS HEARD OR READ about the correct interpretation of Tilakkhana: anicca, dukkha, anatta.
The transition from Sotapanna Anugami to Sotapanna phala can happen anytime after that while one is listening to a discourse; the phala moment registers in the mind in a flash.
This special requirement about Sotapanna phala moment happening while listening to a discourse is something I still need to confirm with a Tipitaka reference. If anyone has that reference, I would be grateful.
It is possible to explain the same thing in many different ways.