Operations Manager, Peter Korisa, said the extension has been made until 26 November while the Manaro Volcano remains at alert level 2.
Ambaeans relocated to Santo and Maewo in early August have expressed their concerns about the care of their crops and animals remaining on the island, as well as how they themselves will cope with the oncoming cyclone season while living in flimsy shelters with inadequate food.
Peter Korisa said the government had very limited resources and he was appealing to the evacuees for calm and co-operation.
"My message to them is just to keep patient and calm and then work with the government and the host communites so that we can find some solution.
"How we can stay until when the level is really taken down to level one and then they can re-evaluate. At this stage level two is still not safe for them so we have to continue to remain on the evacuation relocation sites."
Peter Korisa said if the volcano's activity diminished to level 1 before the end of November, the government would re-evaluate the state of emergency.