Hmm . . .
I, too, have a selection of firmware images for the 2Wire 2700HG* devices and have made them available for download here. (Caution: It's a 63 Mbyte ZIP archive file.) [The archive file has now been removed.]At the back of my mind, I have a vague recollection of the method of obtaining access to the "hidden" debug/recovery mode. It is necessary to apply a jumper to the PCB edge connector at
J2 (see the attached image, below), linking the above and below PCB tracks together. Once the device has been powered up, one needs to use a web-browser to visit the
10.0.0.1 IPv4 address. Your first visit will return an error, so just reload the page. At that
second visit, all should be revealed. (Some fun by the 2Wire "sneaky tricks" department!)
Although the above was revealed to me, by an impeccable source in early 2013, I have yet to try it for myself.
Searching in my "
what not of doings" I have also come across an old
posting, to a different forum, that
may be relevant.