(transitional relief provided with respect to certain fuel tax credits; taxpayers granted until July 1, 2013, to file refund claims in situations where claimed credits exceed tax liability; claim is timely filed if claim relates to credit under I.R.C. Sec. 6426 or payment under I.R.C. 6427, claim is filed on Form 8849, and claimant has or will not make the claim on any other form or at any other time except for a claim that has been previously rejected by IRS due to untimeliness or was repaid by claimant on amended tax return).