Flashing the device

Hopefully not needed ever...
http://askubuntu.com/questions/602035/how-do-i-use-ubuntu-device-flash-with-the-bq-aquaris-e4-5-and-aquaris-e5 says: For production Ubuntu Phone devices, adb has been disabled in recovery, and this affects ubuntu-device-flash operation. You must supply a recovery image with adb enabled, which ubuntu-device-flash will use temporarily while doing its work: For BQ Aquaris E4.5 Ubuntu Edition (aka krillin), use recovery-krillin.img (http://people.canonical.com/~jhm/barajas/recovery-krillin.img) For BQ Aquaris E5 Ubuntu Edition (aka vegetahd), use recovery-vegetahd.img
ubuntu-device-flash can then be supplied with the --recovery-image argument, eg:
$ ubuntu-device-flash touch --channel ubuntu-touch/stable/bq-aquaris.en \
--bootstrap --recovery-image path/to/downloaded/recovery.img
Note that when the command prompts you with:
Expecting the device to be in the bootloader... waiting
You can put a Aquaris E4.5 and Aquaris E5 in the 'bootloader' by holding down Power + Volume Up for a few seconds, releasing the Power button when the red LED lights as the machine reboots, and then selecting 'fastboot' from the device's boot menu.
unknown flag `recovery-image'
If you get this error, that means you are still using an older version of ubuntu-device-flash. Please install the latest version using the ppa:
$ sudo add-apt-repository ppa:phablet-team/tools
$ sudo apt-get update; sudo apt-get upgrade
Last updated: Sat Oct 17 16:11:03 CEST 2015