What lies buried in Pulilan's Libingan?

Famous for its Maytime festival featuring kneeling carabaos, Pulilan in Bulacan was formally declared as a town in 1796. The founding of its church, however, dates way back to 1749. And with this in mind, the cemetery beside the church raises some questions.

According to heritage blogger and advocate Estan Cabigas in Simbahan.net, a royal decree issued in 1787 required local cemeteries to be situated far from church grounds for reasons of hygiene. If the Libingan of Pulilan, as it is called, is really as old as the church, then that makes it a puzzle, given the colonial-era directive.

There seems to be no hard facts about this burial ground, but a look at the entrance arch details unmistakably betrays its Spanish heritage. The back side of the portal also hosts several burial niches, including one which--curiously--rests right above the arch!

Is the cemetery as old as the church? Is the Spanish-era arch really a graveyard entrance or could it have been something else before? Was the cemetery just a later addition, then? Questions, questions...

The cemetery extends to the back of the church, where there are reportedly bullet holes or marks in the wall. Relics of the Philippine Revolution or some other historical event? 

Although disfigured by modern additions like a sari-sari store and unsympathetic metal lettering, one can still appreciate the antiquity of the structure. 

But again, answers to this site's puzzle remain buried, and so more research about the Libingan is needed.