Well then she'll make it to the top of the stairs in peace. She peeks into the second bedroom; is Dudley inside?

No Dudley.

Then she'll put her stuff down inside and start tidying up. How much of a mess is it?

Extremely so. All of Dudley's old games and broken objects are there.

Well then, she'll start sorting for anything salvageable. Anything that isn't, she'll put to the side as neatly as possible. If the Dursleys will let her she'll bag up the broken remnants later.

Meanwhile Dudley screams, whacks his father with his Smelting stick, is sick on purpose, kicks his mother, and throws his tortoise through the greenhouse roof, all to no avail; his parents don't budge.

Poor tortoise. Why did the Dursleys let him have a pet anyway? Sarah just shakes her head and continues her cleaning. Does anything look to be salvageable?

It's Dudley's, if she does anything to it he'll throw a fit but of course he'll never actually do anything with it.

Well worst case it'll be a peace offering to him. She can seek clarification from his parents once she's finished organizing it all.

Well it's getting late...

Then she'll leave the rest of the cleanup for tomorrow and try to get some sleep.

No one bothers her.

She'll get up and get dressed early. She hides her reply letter under her clothes in case she gets a chance to send it. Presumably they won't have installed locks on the outside of her door so she'll set about the beginnings of making breakfast.

They have not done such—she is free to begin her chores, although Aunt Petunia is an early riser as well.

"You're up early."

"I wanted to make sure that breakfast was good today as a thank you for my new room."

"—well. Go along, then."

Sarah sets herself to making breakfast.

And Petunia busies herself with something.

Sarah, eats food as she hurries to make breakfast before Uncle Vernon shows up. Though she's careful not to burn any of the food.

Aunt Petunia goes upstairs.

Sarah will set the food on the table and then make her way out the kitchen door to the garden. Then she'll carefully circle around to the front of the house.

It is as she remembers it.

She'll busy herself gardening, or at least looking like she's gardening, but keep an eye on the vicinity of the front door and frequently glance at the sky for owls.

Here's one.

She jumps up and runs over to the door to intercept it. She'll hold out an arm and offer it as a perch. "Can you take a reply for me?"