https://en.wikipedia.org/wiki/BNC_%28software%29#IRC
tl;dr it's a bouncer and keeps you logged in.
...
In the event that anything worthy of permanence comes up, I shall certainly post it here for posterity.
Usually it involves realtime repetition of collected bits of information already here.
Code:
3:43:57 PM - Radioactdave: Hi folks. I've got a Kindle Paperwhite on 5.4.5
FW. I'd like to jb it. Should I update the FW (flash a newer one) or is it not
worth the hassle?
3:49:01 PM - eschwartz: Jailbreak now, and afterward if you wish to update
the firmware it will be safe to do so without losing the jailbreak.
3:49:26 PM - Radioactdave: Wait, the JB is persistent?
3:49:52 PM - eschwartz: Yes, it includes a "bridge" which is designed to
restore the jailbreak after a firmware update.
3:50:46 PM - Radioactdave: Okay, thanks, seems like I've got to do more
reading on the subject.
3:58:14 PM - Radioactdave: Does the jailbreak survive a device reset via
the menu?
4:45:38 PM - eschwartz: A factory reset removes the bridge, and combined
with a firmware update will completely remove every last conceivable trace
of the jailbreak. Don't do it unless instructed to as part of an emergency
debricking procedure performed over a serial port!
4:46:31 PM - eschwartz: That being said, the bridge attempts to insert itself
for redundancy into the initscripts, for more or less this exact reason.
4:46:46 PM - eschwartz: So all hope is not lost if you perform a factory reset.
4:46:56 PM - eschwartz: As long as you don't get hit with a firmware update.
4:48:04 PM - eschwartz: You can add a few backup files to the device userstore
and the upstart service will perform a self-repair of the bridge.
4:48:13 PM - eschwartz: BUT!!!!!
4:48:16 PM - eschwartz: Why risk it???
4:48:28 PM - eschwartz: Just keep away from the factory reset.
Worthy? Or not?