Different developers can achieve different speeds, and the box speed is usually the highest film speed you can reasonably achieve with the optimal developer. Of course you could be pushing the film and use higher EI, but for some reason Fuji doesn't recommend it with HC-110, or at least they don't list dev times for it. I am 100.00% sure this has nothing whatsoever to do with the fact that HC-110 is sold by Kodak, Fuji's biggest competitor

Fortunately there are other resources available to us which are more informative in this regard....