Friendly warning:
I don't know whether you use "normal" papers or liquid emulsion.... and I don't know what I am to say, applies for "normal"papers..
BUT: (from painful experience): It seems like the bleach contains of two parts: the bleaching, and the tanning/hardening of the gelatine.
And it seems that the tanning/hardening process stops/dies long before the bleach does....
What I do is to bleach a certain amount of papers - if I then want to bleach more, I make a dichromate solution and add this to the bleach - and it works perfectly well.
NOT a scientific approach, but it works for me.
(I tried to bleach about 25 papers (about 8x10) and all looked fine - bleached well, but when I tried to ink the papers no papers were tanned, so I had to through all out... (that's the painful part..))