When a new firmware version is available, then only you update your airport express firmware. When a firmware update is available, you need to open the Airport Utility app. The Utility will immediately show an airport express firmware update that is available for your device by putting a badge on it. You need to then click on your Airport Express and then click on the Update button that appears. Note that the Airport Utility, once installed, will check for updates on its own weekly and notify you if the updates are available. Read More airport bridge mode