Are Sungka and Congkak one underlying mancala tradition carried by migration, or two traditions that converged on nearly the same board and rules independently?

Sungka is described as closely related to Congkak, differing mainly in direction of play, but the documented distribution of Southeast Asian mancala games across two separate waves, an early-19th-century wave into Malaysia, Indonesia and the Maldives and a 20th/21st-century Philippine wave, leaves the exact relationship (common ancestor, direct derivation, or convergent local variants of a shared regional form) unsettled.