J. B., I said:
If the dispatcher gives you a track warrant authority between MP 15 and MP 75, no following train can pass MP 15 until your train has cleared MP 75 (unless both are operating at restricted speed).
But the Trainorders link JBW mentioned points to an online version of GCOR that says:
14.4 Occupying Same Track Warrant Limits
Only one train can occupy the same or overlapping limits of a track warrant except when:
1. All trains within the limits are authorized to move in the same direction and required to provide flag protection behind the train as specified under Rule 6.19 (Flag Protection). The last train may be relieved of providing flag protection when instructed not to foul the limits ahead of any preceding train.
* A train required to provide flag protection to the rear must report to the train dispatcher when it clears the main track before reaching the last named point, unless a flagman is left to prevent a following train from passing.
Flag protection includes dropping fusees from slow-moving trains.
In what little time I've spent around trains in Track Warrant Territory, I don't recall ever hearing a dispatcher authorize this. Track warrants that I've heard have allowed one and only one train in a given stretch.
JAC