REVENUE MEMORANDUM CIRCULAR NO. 126-2019 issued on November 26, 2019 extends the use of the old version of BIR Withholding Certificates/Forms (BIR Form Nos. 2306, 2307 and 2316) by withholding agents, particularly those who generate said certificates/forms through their Computerized Accounting System (CAS) for all transactions covering the taxable year ending December 31, 2019, pending the reconfiguration of their (CAS) which shall not be beyond December 31, 2019.