The Artisan Jr Gent pen (old style no longer sold) used 25/64" and 15/32" bits as mentioned earlier.
The Artisan Jr Gent II pen (current style being sold) uses 10.5 mm and 12.5 mm bits.
Hope this helps!
I'm pretty sure that the discussion was between your Artisan Jr Gent II and what is currently being marketed as Jr Gent I, which you are marketing as the Apprentice Jr Gent. I may be mistaken.
Either way, the suggested bit sizes are as follows:
(Old) Jr Gent, (current) Jr Gent I, Apprentice Jr Gent: 25/64 & 15/32
Jr Gent II: 10.5 & 12.5