The benefits of regular practice of Yoga is endless. It is important to note that we cannot just think of yoga postures and derive the benefits but you should be actually performing it and feeling it. There is no hard and fast rule as for timing is concerned but whatever time you choose, try to stick to that timing everyday. That brings order in your life and your body would appreciate it much better than doing it anytime anywhere. Be good to your body and body will be the best for you.