In principle, I am never against disciples pursuing their education (graduate or post-graduate), as long as they do not neglect keeping association with devotees who inspire them to maintain some kind of devotional sadhana. If she is doing this, then certainly she may continue with her post-graduate studies. This principle is the same, whether it is school, work, or whatever. There is no mandate that somebody must live in the temple and perform full-time duties in the temple. But it is necessary to associate with devotees, especially in the neophyte stages of devotional service, if one wants to protect themselves from worldly association found in universities and workplaces throughout the whole world.
(Collected Letters to My Disciples, Pg 150, 1st Paragraph)