Blizzard have opened up a new WotLK Classic realm specifically for transferring to from select servers, as they also mention further plans for closing certain transfer locations.
Transfer Realm (Source)
To provide players who wish to escape the queues with a pristine environment to begin creating communities together, we have now opened a new destination realm for Free Character Transfers from overpopulated realms: Eranikus (PvP).
This realm can only be accessed via free transfer from Benediction, Faerlina, or Grobbulus. Additionally, all four of these realms are now locked for character creation, which means that it is only possible to create a character on the realm if you already have a character on that realm.
Please note: we will close free transfers to Eranikus when we see it approaching a population that is so high that it might begin queueing. This may occur without a great deal of warning.
Over the last week, transfers to the Sulfuras realm have been successful enough that it is approaching full population. To prevent Sulfuras from requiring a queue, we will close Free Character Transfers to Sulfuras tomorrow, Thursday, September 8 at 12:00 Noon PDT.
Thank you very much for going forth and populating this new realm!
…
Leave Sulfuras open to Alliance transfers only until it’s more balanced.
This is something we’re considering, but we’re planning to close Free Transfers to Sulfuras tomorrow for two reasons:
The total active population is approaching full.
The Alliance/Horde ratio is approaching 50/50.
If that faction balance trend holds, we’ll close Free Transfers and consider it a very fortunate result.
But we’re considering additional Alliance-only free transfers. We’ll see how it looks tomorrow afternoon.