The Absolute
Well-Known Member
Mine never worked until I did the Wifi trick. Thanks for the suggestion!
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So, I wanted to give this a run as well. I am in a 3G only area. With WiFi on, I can power down the device fully and Fast Boot will work. With WiFi off (No 3G connectivity though, terrible signal at my house) I get the slow boot.

Having the same issue. My phone will only fast boot if WIFI is turned on and connected to a network. Don't have 4G here but do when I travel home. I will test there as well.