It’s not all the time. But it does occasionally go to and from the HSR station.
Certain times of the day every day.
I noticed some express airport MRT trains have indicators that go all the way to Huanbei
So it must be in the works to have express go there.
Too seldom though man, never ever managed to get one from taoyuan HSR.
That is a different issue. But they do exist.
Took one this morning that originated in Jhongli