Thanks to Tanvir vai, with an enlightened reference.
Someone created the "MainPage" : January 27, 2004 Edited bn:প্রধান পাতা : January 31, 2004
In between them were MediaWiki updates.
As per the section: https://meta.wikimedia.org/wiki/User:Krinkle/Queries/The_Start_of_Bengali_Wi...