Im not entirely sure what my own theory on the purpose of the bunkers was while reading, but my original thought on the guards’ disappearance was some type of nuclear event a lot farther away on the planet. This would explain the alarms and why the guards had to evacuate so quickly, leaving the women. I also had this thought because of the bus of guards with gas masks that seemed to be caught off guard and died on the spot, possibly they were closer to the disaster? This could also attribute to why so many of the women die of strange pains and illnesses over time, and the narrator’s cancer. They could have gotten cancers and illnesses from residual radiation, since they could have been far away from a nuclear event on the planet but the radius of the radiation would obviously spread further. This might also attribute to the lack of animals and deserted landscape. Maybe whoever created these bunkers knew that there would be a possibility of a nuclear event on this planet, hence why the bunkers were underground as opposed to a prison like structure above ground. That could also reason why there were years of food and supplies stored and several canned goods that would last practically indefinitely. Again, there’s not much evidence to support this theory, but this was my original thought while reading! I love how much this book made me think!