Guild Wars 2

So I have a friend who has a NA account of GW2, but will be oversea in Europe for a couple of months, and is considering to purchase Heart of Thorns – upgrading her GW2 account. Will their account remain in the NA region if they purchase a digital copy, when in Europe? I’m guess that if they were to purchase a physical copy over there, that they may not be able to use that EU cd-key on a NA account.

Otherwise they may have to wait til they return to NA to purchase a physical copy.

Their account is an NA account. If they apply a HoT key to it it will remain an NA account and they will have to keep playing on the NA servers while they’re in Europe.
I can’t speak to the physical copy thing, but a digital copy shouldn’t matter.