A new firmware update is currently rolling for the Sony Bluetooth Keyboard BKB50, designed for the Xperia Z4 Tablet. The new update will move the build number from 1.02 to version 1.08. Sony hasn’t included a changelog, but we have noticed there is now a longer period before the keyboard disconnects.
This short timeout was quite frustrating previously as it meant having to reconnect the keyboard frequently. You will be prompted to download the update next time you pair the BKB50 keyboard to the Xperia Z4 Tablet.