According to the braille commands for Apple, to access the app switcher with a braille display, your supposed to press dots 1 6 and the spacebar, but this command does not work. To get to the App switcher, you press dots 1 2 5 and spacebar. Is this normal or should the dots 1 6 and spacebar work correctly?
You are correct about space with H twice launching the App Switcher. Space with 1-6 launches the side app switcher on the iPad, which is something completely different.