Burning Crusade Classic was originally shown off in February 2021 and its pre-patch went live in late May 2021. This means that we can expect the same to happen for WotLK Classic. The Lich King's expansion was initially revealed on April 2021 which means this would put its pre-patch in late July or early August.

It's also worth noting that thus far, in WotLK Classic's timeline, the game has yet to receive a release date and it's been nearly three months. Contrast this with Burning Crusade Classic's release date, which was revealed in early May 2021—four months after its initial reveal—it could very well mean that WotLK Classic is due for a release date soon, which means that pre-patch would soon follow.

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