That's right. We brazilians say "até amanhã" as if we are saying "see you tomorrow".
"Until tomorrow" is right, but it's literal, can be used in many contexts.
A literal translation for "See you tomorrow" (and used as well) is "Vejo você amanhã" or "Te vejo amanhã".
2019-02-04 In the exercise Eu preciso disso até amanhã, the preferred translation of this phrase is "by tomorrow", yet that is not accepted here.