The core Yi Chuan practice of Standing (Jam Jong) can be practices in any position – standing, sitting or lying down. The purpose is to activate or unite the frame so whole body or Hunyuan strength can be applied from that position. Therefore Yi Chuan practice can take any form, which opens up all sorts of opportunities to practice.
Standing in line at the store, driving, watching tv, lying down but not able to sleep, even while typing on the computer like I am right now are all opportunities to practice linking the frame. Standing or Jam Jong is and never was limited to a set of postures. Rather, the basic eight and other popular shapes are doorways achieving oneness in any position.
The basics are great to focus on during routine practice sessions and are usually shapes commonly used for self defense but keep in mind the main goal of being able to achieve a unified frame spontaneously in any position. Wang Sheng Chai once said that reacting with oneness strength must become spontaneous like being burned by fire swatting away an insect. Using hidden practice time will not only help you awaken oneness strength and develop it more quickly it will also make it more accessible when you really need it.