Vincent96 Is the Duress PIN controlled by the security chip like the auto factory reset on iPhone is controlled by the secure enclave?
No. It depends on the fact that the OS very quickly tries to execute the wipe in the fullest when it's triggered. They say there's no way to stop it once it starts, so from this I'm inferring that they probably store the fact that duress erasure has started, so if the device loses power in the middle of the wipe, it'd try to continue it when it receives power again (and someone forensically examining a powered off device wouldn't be able to know if duress erasure has been started on it, because all stored data is encrypted in Device Encrypted (DE) data).
They've said that if they'll have their own hardware in the future, one good thing they could improve is implementing the duress PIN feature in the secure element.