Talk:Ranked Regulars/@comment-24375795-20140831201403/@comment-5693502-20150208140050

Remember that Leesoo's team already had D-rank status before they even left Wolhaiksong's resort (and that was when they were still on the 30th Floor)(Ch188)

It was never explicitly stated which Floor Baam and the rest of Team Tangsooyook became D-rank Regulars however, with the information given, it points to it being the 30th Floor. Why ? Because immediately after getting on the 30th Floor Team Tangsooyook entered the Workshop Battle.(Ch136) As such, they never took the 30th Floor test(s) that would allow them to pass to the next Floor. Although this can mean that technically becoming a D-rank could lie between the 30th and 35th Floor, the logic and information given would dictate that a Regular would become D-rank upon passing the 30th Floor.

tl;dr 30th Floor is the most likely place where an E-rank becomes a D-rank due to above information.