A survey conducted by the Japanese government has highlighted significant confusion among municipalities regarding how to act on a megaquake advisory related to the Nankai Trough, with 65 percent expressing uncertainty. The advisory, which was the first issued since the system's establishment in 2017, called for heightened disaster readiness for a week while residents continued their daily activities.

Out of the 571 municipalities that participated in the survey, 13 percent admitted that they did not fully understand the workings of the earthquake advisory system, leaving them unsure about the appropriate responses. In light of the inconsistent actions taken by these municipalities—ranging from event cancellations to the establishment of disaster response teams—the government is considering updating its guidelines based on expert recommendations.

The Nankai Trough, where the Eurasian and Philippine Sea tectonic plates meet, poses a significant risk, with experts predicting the potential for a magnitude 8 to 9 earthquake that could trigger extensive shaking and substantial tsunami surges. Following the August advisory, which came shortly after a significant earthquake off the coast of Miyazaki Prefecture, 398 municipalities responded by setting up disaster response headquarters, while a smaller number implemented shelter openings and evacuation orders.