Melon Music Awards 2018 "Top 10 Artists" Winners

That's the data collection period. You didn't read this line: "TOP10 후보의 경우, 주간인기상을 통해 이미 선정된 후보 30팀을 포함합니다."

It says for the top 10, artists that made it onto their weekly popularity chart during that time are eligible. BTOB indeed topped the weekly popularity chart this year, so they are definitely eligible and the data collected from them from December 2017 to November 2018 (regardless of whether the songs were released earlier) are included.

Yeah this is Melon, not Gaon. Gaon Digital also takes into account Downloads (heavy for newer releases) and Streams (Light, Boomerang, Beautiful and Energetic still make appearances on the weekly chart there), and BGM (heavy for new releases and the classic BGM songs). So actual Melon charting is better to look at for this award show.

/r/kpop Thread Parent