Sorry, but this really cracked me up, still laughing ass I type...
The use of test server to reduce bugs going to live servers ended about 6-7 years ago, maybe longer. The feedback on test was responded to by the BB of the time, the information was passed to the devs, and most of the issues on test were resolved before they came to live servers. With a change of ''management'' this system collapsed as shown, for instance, by the number of hotfixes in events - I use the term management loosely as these days I am not sure anyone manages the game, it just grinds along)
Then came the ultimate refusal to accept the feedback being given on test. You loaded Unity onto test2, we went to the time and effort of playing on it for you, gave mountains of feedback letting you know what a failure it was and then....you loaded it on live servers in the same form with exactly the same disgraceful consequences for the players. So to say ''when everything is successful the update lands on the Live servers'' is a total fabrication and distortion of the truth.