The "dot" in Anniversary is used for the sound/letter 'h' as well as the brief form 'a' and 'an'. --Because the word 'a' is used so often in the English language, a dot is used for quickness and easy. --When used as the sound/letter 'h', it is often in front of the outline, but could be somewhere else, depending where the sound falls. It may also be eliminated, depending on the sound and word. Some brief forms or phrases do not use the dot at all.
The 'h-dot' rule is introduced in unit 1 of Anniversary ( gregg.angelfishy.net/anunit01.shtml ) with several examples in paragraph 12. However, it's not well defined in the manual. The drills below will give you more option to learn and practice this rule/theory so you can be familiar with it as you write Gregg Shorthand.