Xperia Blog submitted a new resource: Xperia C5 Ultra_E5553_29.2.A.0.122_Australia_Generic - Sony Xperia C5 Ultra (E5553) Android 6.0 firmware - Generic Australia Read more about this resource...
According to this site (http://www.flashtool.net/downloads.php) users of Xperia C4 or Xperia C5 should not flash their devices using this tool. If that is the case, how are going to manually update devices published on this article. My device is a Sony Xperia C5 (E5553), this post says this is the file I should use: Xperia C5 Ultra (E5553) 29.2.A.0.122 Australia Generic