Why does stabilized CL test as fc instead of cc?

[chem geek]

So, to summarize what I think I read, as FC reacts with the dye, the cya realeases CL so quickly that by the time we read test results, all FC (even that combined with the stabilizer) is made available and reacts with the dye. Correct (even if over simplified)?

Yes, you've got it, except I wouldn't call it FC that reacts with the dye since all of it is called FC, but as "active chlorine" reacts with the dye, the CYA releases more of it so quickly...