Yellow Turban Rebellion vs Yellow Turban Rebellion

I'm playing He Yi of the Yellow Turban Rebellion. I lost an iron mine to an enemy, for a few turns. When I recaptured the mine, I saw that Yellow Turban rebellion was mustering in the area, because the previous owner was unpopular.

This made me wonder whether they were actually friend or foe. The Yellow Turban Rebellion was said to have a positve attitude towards me and we were not at war.

So, I left them alone. They then attack my iron mine. We're still not considered at war after the attack and they still have a positive attitude towards me.

I successfully defended the mine. Their army consisted of 1 general and 6 units. I got every single character of the army, and captured the general. I let the general live, since he kind of seemed to be part of the Yellow Turban Rebellion. He then immediately appears outside the iron mine again, his retinue will return in 2 turns and he now has a second general with 6 new units which are replenishing.

Is this actually meant to function like this?

As far as I know, the Yellow Turbans are more like a bunch of well equipped nomads who sometimes have their own capital but more often than not they don't. They can be a real mess to deal with so I would suggest that you strike their armies quickly to take them out in your area.

Overall strength is negligible but keep an eye out.