Pathlight Connectivity and Battery Life

I have four Pathlights. I have them set as recommended for longest battery life, but I'm only getting 3 weeks out of them before the batteries die, and they all die at about the same time. During those three weeks, the lights are independently losing connectivity and then regaining it within seconds. This is happening constantly. When they regain connectivity, they light up brightly. This occurs only during daylight hours, when the lights aren't even supposed to be on. I'm assuming the battery drain is related to this issue, but I'm not sure how to correct either. They are very close to the bridge, with strong signal in each, and my home network is strong and constant.