Julian Thomas asked:
Would it be that the code point with no holes wasn't used?
The code point with no holes represents the blank character. The code point with all holes is *Letters-shift. *IIRC, Baudot, like ASCII, used mark-hold. So an idle line was carried a continuous mark signal. Characters were represented by 7 elements, (spacing element, five code-point elements, mark element). The mark-to-space transition signalled the beginning of a new code symbol.
Chuck