Thread+BLE,DFU through ble

Hi, nordic engineer:

         Our project has a function, that is, BLE+Thread coexists. We hope that the mobile phone can upgrade the device through BLE. Can this idea be realized?
       I tried to burn softdecvice+bootloader, then use the mobile phone to give the device DFU. After the upgrade is completed, let the device power off and restart, the device does not jump to the application, but enters DFU mode again.