2, 1956, the provincial capital was formally inaugurated, the same day when Delfin N. Montano (the son of former Senator Justiniano Montano) was sworn into office as the new governor. He served in both offices from 1956 to 1971.

On June 22, 1957, the original act was amended by Republic Act No. 1912 increasing its territory to 3917 ha, more or less. Consequently, the municipalities of Indang and General Trias