Being on the Maker schedule doesn't imply being awake at 3 AM.

PG writes of the Maker Schedule: "I evolved another trick for partitioning the day. I used to program from dinner till about 3 am every day, because at night no one could interrupt me. Then I'd sleep till about 11 am, and come in and work until dinner on what I called "business stuff." I never thought of it in these terms, but in effect I had two workdays each day, one on the manager's schedule and one on the maker's."

Does kinda imply he may very well be awake at 3AM. That said, he's also wrapping things up then and unlikely to take on a public Q&A requiring nontrivial attention.

Notice the judicious use of the phrase "used to".