Go by the OP. The tier lists on site aren't always updated in older gens and there are multiple tier lists that exist for non official metagames. It's up to the hoster which is used and so long as they state what the tier list being used for the tournament is, then they can use whichever set it is. Like how all DPP NU tourneys use no Espeon and no Entei even though they aren't banned by Smogon officially.
Smogon's list is out of date, the location I got the list from (UUStadium) Continued to monitor the ADV stats after Smogon finished. Their list is somewhat more representative of ADV NU than Smogons is at the moment.
Lolkomori is subbing in over Celever
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