The secret is in Time and Space.
There is no fixed direction that is auspicious. There is no fixed time that is auspicious. When the direction and time match, then it is auspicious. This is the entire secret in Feng Shui.
The question is "How?!"
There are many good restaurants where people enjoy the good food. The chef in each restaurant claims to have secret recipes handed down from generation to generation. I love food and therefore have eaten in many good restaurants. When I have a chance to chat with the chefs, I find that they all keep their trade secrets tightly and would not disclose a bit. One day I was invited to eat in a canteen and found that the food was exceptionally good. I chatted with the cook and to my surprise he told me he would teach me goumet cooking.
The first lesson I learned that there was no secret recipe to learn.
The second lesson I learned the different kinds of fish in the market place.
Then the different parts of a pig. Then the different parts of a cow. Then different vegetables.
Well, I spent one whole year in the market place with the cook just to learn the raw materials.
Then I watched him cooking different dishes. There was no teaching and no recipe.
Ha! One day the cook asked me, "Did you see any important thing I did in steaming a fish?" When he was satisfied with my observation, he continued to ask me why he did that. He never told me the right answer. He only disagreed with my answer until I got the right answer and the right explanation to the answer.
After many years, I realized that the secret is in Time and Space. The raw materials must be timely. The temperature and other ingredients must be right for the dish.