Regarding Seat Allocation of MDEK 1001 Dev

I have some queries regarding seat allocation after testing more than 30 anchors

  1. I have deployed more than 30 anchors in an open area by keeping approx 10m distance between each other. There i observed seat allocated to each anchor.
    I observed there no seat repetition and from 34 anchors there are always 4 anchors with seat number (-1) allocated , those 4 anchors were not fixed but got shuffled on random basis.
  2. I wanted to know that will there be any seat repetition by increasing distance between them?
    As i gone through the system overview manual:

1.Each anchor needs to be assigned a seat number between 0 and 29
2. No anchor is allowed to hear 2 anchors with the same seat number

As mentioned in manual that no two anchors should hear about 2 anchors with same seat number, but as i understood that all anchors are aware about seats allocated then how it will take place?
Please correct me if i am misunderstood this.
And how to handle that (-1) seat allocation?
Please resolve this issue.