What was the effective date of your son's withdrawal according to the school? You said he was "enrolled Jan-Apr 28." If that's what the school's records show, then he was not enrolled in May.
To be considered a student he only has to be enrolled "during some part of each of any 5 calendar months." So if he was enrolled for even one day in May, that would count as one of the 5 months. But if his withdrawal was effective April 28, he only has 4 months. I don't think it matters when the paperwork was completed. What does his transcript show as the withdrawal date?
