It is true it is hard to achieve fairness in a contest where there are so many variables. There will always be something unfair, I guess. Ultimately it is LINE's contest so they will pick up what they like, probably, which is the way it should be
So I still have faith!
(not that I'd win or anything, but in the relative fairness of the contest) 
Still, I can't wait to see who the winners will be! 
EDIT: While it is true that promoting contest entries is unfair, if you take it as a part of the judging process - stating their preferences already, it doesn't seem that bad, since it battles a little against the re-uploaded series' popularity for example. The judging should have been after September 13th, true, but I would also prefer if the criteria was based on what the staff things instead of popularity, so I find this not that bad, if they really went through all the entries.
...relatively 