Was there a TBC pre patch?

The WoW TBC Classic pre-patch will officially begin on May 18. ... Unlike the original TBC pre-patch nearly 15 years ago, the TBC Classic pre-patch will give players an early introduction to Blood Elves for the Horde and Draenei for the Alliance.

What patch will TBC be released?

TBC Classic will use the patch 2.4. 3 TBC client. This means like Classic, we'll see the end of expansion class tuning, rather than the TBC launch tuning. This won't impact the bosses, however, as they'll launch in their original state, bar any unkillable bosses.