The notice explains how eligible taxpayers can amend prior-year returns to reduce the casualty loss deduction by the amount of the grant, and explains that taxpayers have one year to pay back any resulting tax due, penalty-free and interest-free. To qualify for this relief, these amended returns must be filed by July 30, 2009, and the entire resulting tax due paid by July 30, 2010, in most cases. The notice also provides special instructions for those taxpayers who have already filed an amended return.