So, i believe, the positions which were held overnight on regulars days will not get converted to delivery. Only Options, which were not closed on expiry day shall be converted to physical delivery of shares or short depending what side you are on. Say someone has bought a put or sold a call, then he has to give shares to exchange. He is short and have to give shares with no shares in Demat, what will broker do ? Just my thoughts. May be other members can share their thoughts.