Hessa:
It is already in the rules. Maybe you did not read it properly, "You can't include dramas/movies you watched previously. All dramas/movies must be watched during the challenge period."
Then it must be my limited English as I did read the rules carefully :) For me dramas I haven't finished watching are dramas I haven't watched, so that's why there was the confusion. So to make it clear for me, I have to start watching everything in 2018 and nothing I started previously can be included even though it will be finished in 2018.