Jeff. You're a star....that has done the trick, with a little bit of wrangling.
I was able to boot up, but it gave the following error.
(aruba-lab) #show image version
Ancillary files are not present
*********************************************************************
* WARNING: An additional image upgrade is required to complete the *
* installation of the AP and WebUI files. Please upgrade the boot *
* partition again and reload the controller. *
*********************************************************************
Ancillary file(s) or digest file missing.
Ancillary image is missing please upgrade the image again.
----------------------------------
Partition : 0:0 (/dev/mtdblock9) **Default boot**
Software Version : ArubaOS 6.3.1.9 (Digitally Signed - Production Build)
Build number : 44832
Label : 44832
Built on : Tue Jul 15 12:57:37 PDT 2014
----------------------------------
Partition : 0:1 (/dev/mtdblock10)
Tried to upgrade partition 1 but this failed giving the following.
Upgrading partition 1
Secure file copy:....................................................
.....................................................................
File copied successfully.
Saving file to flash:
........................
Error upgrading image: Couldn't erase image partition
So I upgraded partition 1 via cpboot method which seemed to work, but this time I made sure I didn't boot into that one. I booted into partition 0 and still got the message about Ancillary Files missing etc.
Upgraded partition 1 via normal method in cli and this seemed to work.
Changed the boot statement to load partition 1, reloaded and crossed fingers.
All good now. :-)
This all started when I couldn't upgrade due to insufficient space, despite clearing all files out. I suspect that if I had done a 'write erase all' and the restored the flashbackup I wouldn't have had the problem.
Anyhow...lesson learnt. Good thing it wasn't a customers equipment.