World Records, seconds under 60-second pace:
200m: 10.81
400m: 16.97
600m: 17.19
800m: 19.09
1000m: 18.04
1500m: 19.00
2000m: 16.87
3000m: 12.45
The "expected" behavior is for the gap to grow smoothly until it reaches a certain point and then reverse. For short races, the distance is too short to get very much under 60-second pace. For long races, the pace catches up to you.
You can see that this is basically what happens, with the margin getting bigger, stabilizing around 800-1500, and then decreasing. But the 1000m margin is slightly less than either of the surronding distances.
All of this is to say that, while an excellent record, the 1000m is (perhaps unsurprisingly) weaker than the 800m record and the 1500m record. In other words, it's ripe to fall to an outstanding athlete like Arop. The race will have to go perfectly, of course, and that usually doesn't happen. But if it does, we could see something very big.