What does the phrase "half seven" mean?
Half seven is the same as half past seven, with past simply missing. It's 7:30.
Americans say "half past seven". I've never heard anyone say "half before seven" nor have I heard an American say "half seven". It does lead to odd situations. My German wife has a very good English friend. She learned the difference between "half seven" and "halbsieben" when they both showed up on time yet an hour apart.