As UPS and the Teamsters union stall over contract negotiations, it’s possible that workers will begin to strike on July 31, which would affect a vast number of book shipments to and from publishers. The American Booksellers Association suggested ways bookstores can prepare: This month, stores should order up on inventory, order stock for Fall author events, coordinate returns (even if they don’t use UPS), and ask publishers for an increase in their credit limits.