That seems way too convenient
I think it is a "Who, Me", but one who thought he'd be smart by shortening the change window by doing some "harmless" pre-work to prepare, and it turned out whoever designed the plan knew more about things work and already shortened the in-window work as much as possible.
Over my years of consulting I can think of more than a few times I created carefully scripted changes that were to be executed by on call or offshore staff overnight or on a weekend, who screwed things up because they went off script. And I've seen it happen when I wasn't directly involved more times than I can count. A few cases were like this, trying to do steps they thought were harmless before the window to complete the change more quickly.
There are always those people who think they are more clever than they are, and want to complete something planned for x time in x/2 or x/4 time so they take shortcuts from planned/established procedure thinking they will be rewarded with praise and attention. Well, they get the attention at least!
This guy was better than most because he was somehow able to deflect blame to the "rare race condition happened a half hour before we were going to make the change"!