Its all guess work a lot of the time...for all we know shorts might have covered off even more, August 7/8 the PPS got up around $3.75....perhaps short interest was whittled down to one or two hundred thousand at that point, followed by more shorting after to push the PPS down and stall the move up....
Possible? IMO absolutely, but no way to confirm or refute it......nobody would admit to it even if it did happen.