Hermione ultimately did not sign the list to stay at Hogwarts over the holiday, and instead boarded the Express along with the other departing students.
The reason was quite simple: whether she chose to stay in the dormitory or set up a tent in Avalon, Hermione's every move would inevitably draw the notice of her peers. If she were to suddenly vanish for an extended period, most people might not ask outright where she went, but they would undoubtedly feel curious or suspicious.
This was a situation neither Hermione nor Albert wanted to see, for when someone acts overly secretive, the exposure of their secrets is never far behind. Rather than risk that, it was better to simply find an excuse: visiting her family in Australia.
Chapter 1498