The firmwares are under the Andy subforum...
But, a common theme around here is don't fix what ain't broke. If the camera is working and meets your needs, in many instances an update breaks what you had working and provides you with something you didn't need. A Z12E that someone updated and then constantly reboots comes to mind, and a certain PTZ that loses autotracking with an update come to mind, a Hikvision ANPR camera losing half the FPS and ability to read US plates - those are big deals to have happen. Don't do it unless it is fixing a problem you are experiencing or adds a feature you really need.
All of these mentioned users had perfectly working cameras for their need until they updated just for the sake of updating...