There is a post available on XDA with links to the latest Droid 4 Leak. You can either follow that thread or use the tool I've written here to update to the latest leaked version.
[HOW TO] Install the leaked Android 4.0.4 ICS build on the Droid 4 (XT894) - xda-developers
I have created and tested an update utility that will pre-flash GB 219 files to your phone plus the 215 leaked kernel enabling you to update to this latest version using the recovery option on the phone. The tool is available below for windows only. However, you can easily read through the batch file and copy/paste the commands to a console in Linux provided you have the phone tools installed.
This assumes you have updated your phone before and know how to extract and copy the "blur...." file from the leak archive to your phone. It also assumes you know what CMD is and at least how to navigate the directory structure using a drive letter and/or the cd command.
- You'll need a copy of the latest DROID4 leak 6.16.215 available here:
Unpack and copy the blur...zip file to your phone sdcard.
- You'll need a copy of the 6.16.215 kernel ONLY at one of the links below:
This will be flashed to your phone, no need to copy it to the sdcard.
- You'll need a copy of the Gingerbread 219 OTA update available at one of the links below if you don't already have one:
- You'll need a copy of the UPDATELEAK tool here:
- Unpack the tool and read through the README.txt file.
- Copy necessary files from GB 219 to the UPDATELEAK directory.
- Copy the boot image for .215 to the UPDATELEAK directory unless you saved it there.
- Double check you copied the leak update to your sdcard
- Connect phone via USB, enable USB debugging, set USB mode to "camera".
- Run "menu.bat" and enter "1", then read the prolific warnings and answer "y" to continue.
After flashing BEFORE REBOOTING with phone still in ap-fastboot mode...
- Run CMD (windows command prompt) and enter final command to write boot image. (tool supplies the command or see below)
NOTE you must navigate to the UPDATELEAK directory in cmd for the flash tool to find the boot image and work properly.
This command writes the target boot image to the phone.
- Reboot phone and wait while it updates (you will see animated android and progress bar). Wait some more...
- Turn off phone (down vol and power buttons) then re-start in bootloader mode (both volumes plus power)
- Select Recovery, Install from SDcard then select the 215 update file on phone and let it install/update.
NOTE: If you see the red broken android animation and/or don't see the vertical menu with update from sd on it you may need to hit both volume keys to get it.
This tool requires you to enter and run a single command using CMD.
The final command is: fastboot flash boot boot-6-16-215.img (assuming you are installing ICS 215 leak)
After it finished and you observe the word "writing" either manually reboot or enter: fastboot reboot via CMD.