Fairly sure 3 steps is the limit
"Each competitor must keep in the lanes outside the line or curb marking the inside of the track, including the curved part of the diversion from the track for the steeplechase water jump. In races run entirely in lanes, each competitor must keep in the allotted lane from start to finish. In races run partially in lanes, each competitor must keep in the allotted lane from the start to the marked cut - in points. Unless a material advantage has been gained or the athlete is in violation of Rule 163.4, a competitor shall not be disqualified if he or she:
(a) Is pushed or forced by another competitor to step out of the lane, or
(b) Steps out of the lane on the straightaway, or
(c) Steps or runs outside of the outer lane line on the curve, or on any traight part of the diversion from the track for the steeplechase water jump.
Excluding the above exceptions, the Referee shall disqualify a competitor if an Umpire reports that the competitor has stepped out of the lane."
technically should be a DQ, unfortunately. 9:15 in extreme heat holy shit - she would WIN worlds.