She began to have hallucinations of a former friend appearing to her during her studies, though it was later revealed to be a being attempting to communicate with Tilly via the Mycelial network.
Tilly’s outbursts due to the situation were forgiven, but her progress in the program was never touched on past that point.
Tilly had been accepted into a special program for Ensigns wishing to advance in Starfleet in Season 2 of Star Trek: Discovery but had some struggles under pressure.