To be fair, this isn't a "small" update. If I understand it correctly, this is the full morning, so it's no different than before when he was splitting the day up into quarters.
It just seems like another odd structural decision. "Hey, I'm going to change to an event-based release schedule. Except for the very first update of Part 2, that's going to be the full morning just like it was before."
Again, the next update will tell us a lot about his output, but maybe we've been asking the wrong question. Instead of asking why this update is taking so long, maybe we should be asking why the script wasn't structured to make better use of the event-based release schedule to minimize development time.