for the past few days Ive been doing the HS and i noticed that some bots are mining rather than fighting, then I noticed that some of the NPC group members are mining too. seems like a bug, I suppose.

Not really a bug , the idea is that the Hive and the faction are fighting over the resources in the sector.

oh...well it still seems odd to see bots and corvus mining in a huge battle. but it makes for easy targets so I wont complain.

I wonder if that would become clearer if more mining 'taurs jumped into the system after the Hive is evicted. Is that explained in the mission text? I can't remember.