Swytch on a Brompton

Good morning. A friend's bought an audio Brompton electrified by a Swytch kit. In general she's very happy with it, but she says it doesn't give enough power when she's going up a steep hill.

As far as I can gather, the 5 levels of pedal assist work on flat roads, but on steep hills, only full throttle with no pedalling works.

Is this normal?