IIRC he stated, in this thread, that his first chips came from a shared wafer at a university.

Some quantity from a portion of a wafer, not 'a few wafers' as a test run at a commercial fab in preparation to just cranking out commercial amounts from the same fab.

I have no idea what would be involved in moving from a proven test run from a 'shared university wafer' to x number of wafers at commercial fab. But there is bound to be some delay. And risk.