It's not unusual for me to get applications where the post-cal is larger than the pre-cal, because they didn't do the measurement until the afternoon and didn't post-cal until the early evening.
That being said, I would be fine if they did just one post-cal ride if it came up 5 or more counts smaller than the pre-cal average. That happens to me quite often on my first post-cal ride, and it is a total waste of time to ride it 3 more times when there is zero chance the average will be larger than the pre-cal.