A taxpayer received an assessment notice from the BIR on February 3, 2009. The following day, he filed a protest, in the form of a request for reinvestigation, against the assessment and submitted all relevant documents in support of the protest. On September 11, 2009, the taxpayer, apprehensive because he had not yet received notice of a decision by the Commissioner on his protest, sought your advice. What remedy or remedies are available to the taxpayer? Explain.