The most sensible interpretation of that quote is that the loan could be extended if Allegri remains unconvinced that he merits a spot the in squad next season, due to lack of game-time or unconvincing performances. The idea that Juve is doing a straight-swap of a promising young player with Howedes, who will cost about half what Pjaca cost, simply because he had a bad injury, regardless of how he bounces back is ridiculous.