PT, you must have gone to school and learned the "New Math" or some other weird "progressive education" thing.
25% over 16a is 20a. Show your work! ok. 1/4 of 16 is 4 add 4 to 16 and you get 20. Now 20 is 20% over what? Like the non -progressive education text-books said (before they were banned by NDP union teachers)--"The easy solution is left to the student."
EDIT--Blue Sky manual should be followed of course if that is what you have. MorningStar MPPT says go ahead and run it to the rated amps but if you buy more panels than that, you won't get any more amps to the battery, so don't waste your money. Are you sure it is not the same with Blue Sky MPPT?