Bornakk, a Blizzard CM, posted in the official WoW Classic forums that they have rolled out a hotfix for a Warsong Gulch issue that was affecting the queue.
The hotfix makes it so that placement in the queue is reset when adding new players to a group while already in queue.
We are in the process of deploying a hotfix to address an issue affecting the Warsong Gulch queue in WoW Classic. After the hotfix, adding players to your group while already in queue will reset your place in the queue. If you are in queue for WSG or AV when this hotfix is deployed, you may be dropped from the queue and will need to re-queue. Thank you for your patience.