[Bringer]

One of my testers has a Battlenet account with WoW accounts in both US and EU regions.
The tester confirmed the following query of her exact setup and results.

Just to make sure I fully understand.. from your home in the UK
You have one Battlenet accountID
in that account you have two EU-Wow accounts. a US-Wow account starter account, and a WoD beta account
You have a single copy of WoW installed for the live accounts and a copy for the WoD beta account.

You launch with battlenet desktop app
you login using your battlenet accountID

At the battlenet games starter screen...
with Wow selected you select your desired WoW account and press the PLAY button launching the WoW client.

On launch you are logged into the WoW client and are at the character selection screen of the realm you last played.
Assuming you want to play on a different realm you press the CHANGE REALM button and get the realm list for the region associated with your selected WoW account


Once in game on a character selected running our addon or running the script
/script local rk = GetCVar("portal") == "public-test" and "PTR" or GetCVar("portal"); print(rk)

You get the expected output of EU while in the EU region, but you still get the output of EU when in the US region?
While looking at WoD beta the script prints PTR

Changing the Battlenet region before logging on to Battlenet has no impact on the results.