Reading the FAQ, I found this:
I don’t know what’s a typical doorbell height for old construction and whether mine is atypical or like most. Is 1m vs. 1.4m enough out of range to be problematic?How should the Smart Video Doorbell be positioned?
The Smart Video Doorbell is designed to replace your doorbell button, without changing its location. If, however, you are installing a doorbell for the first time, we recommend that you install it near your front door, around 1.4 metres from the ground.