blog.mbirth.de

BlackBerry/TCL has disabled the described method of gaining access to the advanced features of the Updates app in the firmware versions of October 2017 and later. However, there's a way to still get access using the Janus vulnerability and installing an older or patched version of the updater. But this, too, will be gone after the December 2017 update.

USE THESE AT YOUR OWN RISK! Especially the Engineering Mode has a few options which can trigger DTEK (showing your OS as compromised) and probably do worse.