All versions of Rodinal contain Hydroxide, right from its introduction however most of it reacts with the metabisulphite to form Sulphite, and the Calbe version has no excess Hyrdoxide.
Section 9 of the PDF you've linked to clearly states the pH of the APH09 concentrate is 11.8, unless you add more Hydroxide it can't go higher with dilution.
Ian

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