After spending a night at the inn in Fengs Village, Sun Yixie and Huang Donglai hurriedly set off, continuing their journey southwest.
The next day, they traveled from Yan State to Jining.
Now, this place Jining was a "Prefecture" in the first year of Emperor Ming Taizu and Yan State was subordinate to Jining Prefecture at the time. However, later on, Taizu conferred the title of Prince Lu to his tenth son and made Yan State a vassal there. Thus, Yan State was promoted to a prefecture, while Jining was demoted to a state.
Basically, these two places are right next to each other, and as far as administration goes, it's a toss-up as to which encloses which. You'll get the picture if you look at a map, so let's not belabor the point.
But here, we still need to talk about this "Prince Lu."