Having the app added to the deep sleep mode list should not have an impact on the stored data within the app; including the device ID.
The Device ID is generated when the app is installed on the mobile device. A new Device ID will be generated if the device is uninstalled and then re-installed.
From the Pure Access manual: https://manual.pureaccess.com/pure-access-manual/1/en/topic/isonas-mobile
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