That might be happening some, Gene, possibly with retail shorters, but the IH Short Shares have been getting out, in large numbers, since June, eight months ago. I believe that these numbers are part of a bigger trend than just this quarter's report.
I am not sure that increasing your short shares position before the quarter report would protect you. Borrowing on short shares ahead of the report could put you at a much bigger risk if the report is good and the pps rises. You would be instantly caught in a hole and forced to bail to prevent a bigger loss.
It would be wiser, imo, to borrow your short shares after the quarter report to prevent surprises.
It would be the same for buying Long shares. Don't buy ahead of the quarter report if you are not sure of the outcome. Buy after the quarter so as not to be negatively surprised.
I believe that is why the Institutional Holders tend to bring the pps to the mean, 20 MA before the quarter reports; to prevent any bad surprise.
JMHO.
Capt.W