"Playing by the Rules" A Vox article on Advance Parole
Technically, without legal status, if Pacheco were to leave the US she wouldn't be allowed to return. But she could get something called "advance parole," which is basically an official promise from the federal government. If someone is traveling for a particular purpose — a semester abroad, a business trip, an ailing or dead relative — "advance parole" says they'll be let back into the US when they come back. Advance parole isn't something people apply for all that often, especially for professional reasons, but it's well established (for people who are waiting for their green-card applications to be processed, for example).
The article shows a great deal of insight into the difficulties of attaining advance parole and the role it plays for those who are undocumented but are protected from deportation under DACA. To read the full article on how going through Advance Parole affected Gaby, read the article here.