Sirius had gone into the Ministry to speak with Griselda Marchbanks's people in the Wizarding Examinations Authority to find out exactly what the Grangers needed to do so there were no loopholes someone could exploit against them when she withdrew. It turned out she only needed to make sure she'd earned the minimum required number of OWLs - she'd earned far more than the minimum - and send a formal letter, signed by her guardians, to the Deputy Headmistress/master stating her intent to withdraw. While there he was also able to collect a certified copy of her OWL results.
Because Hermione was considered a muggle-born and her guardians were non-magicals, and it did not specifically state it wasn't meant to be anyone but her magical guardian who made that determination, Sirius requested and became her magical guardian via the Wizarding Children's Services. Then both he and both her parents, plus Hermione herself, co-signed the letter. Sirius then sent that letter using Hedwig direct to McGonagall, just as he knew the Grangers' aeroplane was taking off from Heathrow Airport.
When McGonagall received the letter, she carefully read through it and sighed in extreme disappointment before setting it aside. It joined a small stack of similar letters from others.
The letter covered everything that 'went wrong' and specifically listed out and numbered each law and/or school rule that was broken by the staff - especially the Headmaster and her regarding her, Hermione, and what she personally and specifically witnessed.
It also covered how she now had her OWLs and was free to withdraw, but did not state she was transferring to Ilvermorny; and would be 'seeing what she could do to further her education in non-magical schooling', but did not state outright she would be attending a non-magical school.
In the past, McGonagall would have taken the letter direct to Dumbledore. However, after what came out of the trials concerning how much Dumbledore was to blame for Harry's death - and of which she knew herself to unwittingly being a party to - those days were over. In her mind, Dumbledore would now be told as little as possible.
She was already working out how to do that so he wouldn't know Miss Granger would not be attending Hogwarts until the First of September.
Another to receive a personal letter from Hermione, co-signed only by Sirius this time, was Professor Filius Flitwick. As well as being both a Duelling Master and the Charms Master of Hogwarts, he was also the Head of Ravenclaw House.
The letter detailed what they knew of the near-unrelenting bullying Luna was suffering from; the ongoing thefts of her personal effects, the verbal taunting, the deliberate destruction of her assignments and other school work, etcetera.
Then, in the letter, Sirius wrote it was to stop immediately - or he would personally challenge the little Duelling Master to a public duel.
What really set a fire under Flitwick's bum to immediately do something about the bullying was the line in the letter from Sirius regarding the duel which stated: 'It will, of course, not be an honour duel; because anyone who would willingly allow a child under their direct care to be constantly bullied has no honour.'
And Flitwick did not wait until the students returned on the First of September to address the issue, either. For the magical-raised, he was on the floo and visiting students and their parents in their homes that very day. For the muggle-raised he went to their homes by apparation. It took him a few days, but he got it done.
His final visit was to the Rookery, Luna's home she shared with her father, to speak with her and her father about it.
Before he even asked her if it was going on - he didn't need to as he now knew it definitely was he was offering his personal apologies to both her and her father for the way in which she'd been treated over her past four years. "This stops immediately, Miss Lovegood," he firmly stated. "Even if it is, as you believe, the Nargles who are responsible you are to inform me immediately if it happens again. I believe that I will definitely be able to do something about it.
"However, I have already visited and spoken with a number of your fellow Ravenclaw students and they will now also be helping you and protecting you while at the school."
Luna, with tears of relief in her eyes, could only nod back and utter a very quiet, "Thank you."
Though not asked to, Flitwick had sent a letter back to Sirius informing him of what he had done and what would now be happening.
Sirius's response, less the headers and footers, was a short note of effectively only four words, 'It's about bloody time!' Once August rolled around, Ron's mother was now on his back to get his homework completed.
"Get it done or I'll let your father know you've not even started it," his mother declared. "You're already on probation within this family and you don't want to give your father any further excuse to kick you out of it."
As it had been over a month since his 'whipping' at the hands of his father, the memory of how much pain that had caused him had dulled. However, the memories of how he couldn't even sit for days afterwards had not faded.
Moping about it, he made his way up to his room.
However, instead of immediately setting-to and starting on his homework, he wrote a quick letter to Hermione to come visit 'so we can remember Harry together. And, Mum's okay with you coming and staying until we go back to Hogwarts. Isn't that great? It means you can get away from the muggles!'
Happy he'd not let on he really only wanted her to visit so she could help him with his homework - that is, actually do his homework for him - he took his letter over to Pigwidgeon.
After attaching it to the owl's leg he carried it over to his open window and said, "To Hermione Granger in London, Pig." Then he lofted the little 'featherball' out his window and away.
However, as he was about to close his window he noticed Pigwidgeon seemed to be flying about all over the place.
Frowning at it, he muttered, "Stupid bird."
As he then pulled out his books, assignment notes and clean stationery so they'd be on the desk and look like he actually was doing his homework if anyone walked in, he also pulled out a Quidditch magazine. He'd 'found' it in the Gryffindor commonroom the day they boarded the train to leave the school and had immediately stuffed it into a pocket of his robes as something to read over the break.
It must have been less than a minute later when he heard his Mum screech out, "RONALD BILIUS WEASLEY!"
So surprised he almost fell out of the chair he had rocked back on while reading, he quickly scampered down to the kitchen and to his mother. That voice she'd used was the one that promised significant pain if it wasn't immediately attended to.
As he rushed into the kitchen his mother was glaring at him.
"Mum?" he warily asked.
Holding her off-hand aloft, Ron could see she was holding a crumpled letter in her hand. "Explain to me, Ronald, why it is you think young Hermione needs to get away from the muggles? And, just when did I give my permission for her to visit here this year?"
Ron winced.