I did not make a backup of anything. I don't even know what a "TA partition" is. Never heard that term in my life. Just like about 80% of the things mentioned in the installation instructions.

Look, I also went though this a while ago and don't remember all the details, but I do remember it took me a good part of a whole day to complete it. There were many outdated links and other things I had to look up for myself, because they were not sufficiently explained.

Some examples: the instructions mention you have to download Emma, whereas in reality no such thing was necessary since the flashing tool was included in the downloaded zip. it was never explained what a "fastboot driver" is and why do I need one. As it turned out, following the instructions and installing it was a grave mistake as the process worked much better without it. The instructions for getting the unlock keys mentioned I had to give Sony my details but none of that happened, making me waste time trying again because I was assuming I did it wrong. It was never explained what "vendor binary images" are and why do I need them. The fact that you will get an outdated version was mentioned only at the end and only as a "by the way".

But first and foremost of all, the instructions are badly structured. I would have written them as a list of steps with a short explanation what it is and why is it needed. Then, and only then, would I go into details of each step. The way the instructions are written makes even reading them a pain. It looks like it was written by someone who wanted to jot them down quickly before he forgets, rather than by someone who knows how to write user manuals.

Anyway. You say it was easy for you. That either makes you a genius or me an idiot. I can live with both