This is embarrasing to ask: is a special octave sign required after every print page indicator, or only when the number is included?
I’ve search De Garmo and MBC ’97, but there seems to be no direct mention of this, and none of the Drills involve a same-octave page change in single-line format to provide a model. Since a page change doesn’t seem to constitute a major interruption I’ve always assumed that a special octave mark is [u]not [/u]required, but I have to provide proof.