In Presbyterian churches, are the office and elder and deacon permanent or are the only for a limited length of time. In the church I'm attending it seems (I need to confirm) the the elders and deacons are replaced every year or their term is extended. Is this normal practice or is it dependent on the individual church? I always thought it was more of a permanent position, but I have never really given it much thought. Anyway, a year seems like a very short period of time.

Thanks,
John