SECTION 1. The provisions of existing law to the contrary notwithstanding, and subject to the special provisions and limitations hereinafter provided, the provisions of Republic Act Numbered Three hundred forty, including all amendments thereto on the date this Act takes effect, shall be and are hereby made applicable to persons (1) retired under the provisions of Commonwealth Act Numbered One hundred ninety, or (2) honorably separated with gratuity under subsection (g), section twenty-two of Commonwealth Act Numbered One, otherwise known as the National Defense Act, or (3) retired under Republic Act Numbered Three hundred forty with effective date of retirement prior to January one, nineteen hundred fifty-five, or (4) retired under Act Numbered Forty-one hundred fifty-one, and which persons—
were in the active service of the Philippine Army or any guerrilla organization duly recognized as a component thereof, at any time between December eight, nineteen hundred forty-one and September two, nineteen hundred forty-five; and
had completed at least twenty years' active service on the date of their original retirement or separation: Provided, That persons separated with gratuity on account physical disability under subsection (g), section twenty-two of Commonwealth Act Numbered One who had less than twenty years' active service on the date of their original separation, shall be entitled to the benefits of the proviso contained in section eight of Republic Act Numbered Three hundred forty.