This is a simplification to make the calculation more straightforward. But a typical US workplace honors about 11 to 13 federal holidays. I assume that an AI does not need a vacation, but can't work 2 days straight autonomously when its human handlers are enjoying a weekend.
There are no human handlers. From the opening paragraph (emphasis mine):
> We built a Software Factory: non-interactive development where specs + scenarios drive agents that write code, run harnesses, and converge without human review.
[Edit] I don't know why I'm being downvoted for quoting the linked article. I didn't say it was a good idea.