A historian told me that there were mass reversions from Catholicism in Luzon in the French case, the Spanish and the nobility ruled the philippines side by side, so a split between Luzon and visayas is possible since in the 17th century only the lowland coast was conquered, pagan reversion is possible which was mentioned to me by a historian due to failed attempts b4 19 th century and isolated areas remain pagan and those pagans were was completely pacified shortly before the 19 century.