Most likely reason for the two films would be that two different registers were being used concurrently, one as a 'back up' of the other. Many of the denominations used (and still use) two registers. For example, when marrying in a church, the bride and the groom are still often asked to sign three or more registers. One will be the civil register, and the others will be the parish register and its back up. The parish registers are often required to be stored separately from each other, both in fireproof safes, so say one would be kept within the Church building, and one at the clergy's manse.
The Early Church Records are, of themselves, interesting. Back in 1810, Gov Macquarie issued a general order requiring all the clergy (of all the denominations) to transmit records of baptisms and burials (and later added marriages) that they celebrated back to the NSW Chaplains. So, at times it may seem that a bdm event occurred at say St Philips C of E, Sydney, when in fact that was simply the NSW Chaplain recording a transmission from a clergyman, including not just the Protestant denominations, but also Roman Catholic ceremonies. Many of the apparent 'duplicated/triplicated/quadruplicated' entries at NSW BDM 'pre 1856' (ie the V series) are simply the recorded transmissions from the outlying districts. One of my 1810s ancestors has FOUR entries for her baptism. So I have four different films AO (NSWSRO) reference nos. for those. (Add and each has a slightly different piece of 'gleaned' information about either herself or her parents)
Cheers, JM
