From all the breaks, up to that point, it’s clearly apparent he’s having problems just keeping on teleprompter. My most probable guess is, he finally ran out of steam from all the takes, and had to get another shot of whatever cocktail of stimulants he gets loaded up with so he could finish. And with all those edits, there’s no telling how long it takes to get him back on his feet if they could at all, for each take they then splice together.