Notice of Filing and Immediate Effectiveness of Proposed Rule Change Amending NYSE Rule 128, Which Governs Clearly Erroneous Executions, Extending the Effective Date of the Pilot Until September 30, 2013 and Adopting New Paragraph (i) to NYSE Rule 128 in Connection With the Upcoming Operation of the Plan To Address Extraordinary Market Volatility Pursuant to Rule 608 of Regulation NMS Under the Act