It's essentially the same one, but as the existing flows cool (especially during periods of reduced activity) they create obstructions to the previous flow forcing it to move away from the original track. The top of the flow can also cool significantly creating a roof over the stream for a long stretch and a "new" vent further away from the cone. But it's all part of the same giant crack in that part of the island.
In this video:
at 0m13s-0m17s you can see how this eruption's lava is flowing around, and now into, an old cone. The lava field is spreading out a little, but it's pretty much restricted to same area that this collection of volcanoes has been modifying for the last few million years. Not really the kind of place you'd want to build a house, but people did (same way as they build on known flood plains in wetter parts of the world ... )