Hi, Sophie! I'm not an admin, so if they tell you something totally different, feel free to ignore this!
I know we have
this thread that gives options for muggleborns! Maybe she could've transferred to Beauxbatons?
Of course, starting school her second year could also work, although if she didn't formally tutor and/or go to Beauxbatons for her first year, she'd be starting as a first year, so there's always that! There are several characters who went on the run and returned later, to repeat years when the return!
There's also the option of her finding someone to tutor her, so that when she DOES finally enter Hogwarts, she starts as a second year. Reece was already a student at Hogwarts, and I chose the running away option AND the tutoring option, so when he returned to Hogwarts after almost two years, he picked right up where he left off.

I'm sure if the admins have something else to say, they'll chime in, too!
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