Strict mode does not allow Australian 1300 XXX XXX numbers

Using the demo at https://intl-tel-input.com/examples/strict-mode.html, selecting Australia as a country and typing in a number such as 1300123456 doesn't allow the final number (6) to be entered, despite this number being valid as per https://libphonenumber.appspot.com/phonenumberparser?number=1300+123+456&country=AU.