It's fairly obvious that what IRS meant is that the deduction is NOW available, when they wrote NOT available.  You conveniently did not quote the sentence that followed:  

"If you already filed your return for a prior year and now want to claim the deduction for that year, you can do so by filing an amended return on Form 1040-X, Amended U.S. Individual Income Tax Return. Amended returns can't be filed electronically and can take up to 16 weeks to process."