Can someone confirm if the steps described in http://bb.osmocom.org/trac/wiki/flashing are still valid, as I can’t find “loader.e88loader.bin”. I’m using sylvain/testing branch.
Probably not.
And unless you know how to recover things with JTAG or have a lot of spare phones and you're ready to brick a bunch of them, I wouldn't even attempt flashing.
Both the code and the instructions related to it are pretty much unmaintained / untested and use at your own risk.
Cheers,
Sylvain