New software with firmware build 10.5.1.A.0.292 has been released for the older Xperia Z series. The update moves the build number from the current version (10.5.1.A.0.283) and as the small change in build number suggests, there are no tangible changes. It is likely therefore to be a bug fix update only.
The update is currently live for select regions on the Xperia Z, Xperia ZR and Xperia Tablet Z. The Xperia ZL is still yet to receive the update. If you have updated your handset, let us know of any changes in the comments below.