Ye Jun went through a hectic month, using all the time to improve and catch up to Ye Chen and others. It led to him ignoring some things he wouldn't have normally noticed.
Now that he was free, had time, and could experiment, he was discovering new things. As he was processing the Fallen Star Sword Art, he realized he could actually learn all of it by himself.
In layman terms, he basically got the foundation ready to make a building upon picking an attribute of some technique. From there, he had two options to complete the building entirely.
Either he could steal the materials from others or buy his own. In the cultivation sense, he could either copy the attributes to progress faster and with less effort, or simply push forward with his own effort.
The second method was difficult to accomplish, but it left open room for him to progress. A good thing since he couldn't get those attributes indefinitely.
