Flagging a test is always a possibility, but there is usually more than a mere higher score. When a score shows a rapid progression, chances are that the “system” will review the seating chart (or the cheating chart if you will) A 1700 to 2000 rise will not necessarily trigger a review of the score, but if a student shows a 650-700 verbal score but a truly subpar essay, the odds of a review increase.
All in all, this is NOT an issue to worry about.