He left the Wulfhall at eight fifteen on the morning of the fourteenth.
He did not tell anyone where he was going. This was not an oversight — it was a decision he had made in July when the plan had reached the stage where it was real enough to be possible. The people who would have wanted to come were the people whose presence would have required him to manage their safety alongside the task, which would have doubled the list of what could go wrong. The people who would have tried to stop him would have had arguments that were reasonable and that he had already heard and considered and concluded were less significant than the need to get the Cup out of Bellatrix Lestrange's vault before September.
He told Sable he was going to Diagon Alley and would be back for lunch, which was accurate in the sense that Diagon Alley was where Gringotts was and he intended to be back for lunch.
He Apparated to the Leaky Cauldron at eight twenty.
The August morning was warm, purposeful, the alley doing its work with the density of August crowds that were neither the tourist peak of July nor the school-year thinning of September. He moved through it with the calm of someone who had a destination and a plan and was implementing both.
He had prepared for ten days. Not the plan itself, which had been in development since June — the specific preparation of this particular morning. He had run through the steps in his head every evening for a week, later practicing the steps till it became muscle memory.
He had calibrated the Imperius hold for the specific duration of a Gringotts vault visit. The standard cart journey to the upper-middle vaults took approximately twelve minutes each way. The vault access itself — the door, the interior, the retrieval — he had estimated at fifteen minutes including the counter-curse work and the containment. Forty minutes total, with a ten-minute buffer for variance.
He had practiced the Obliviate precision he would need — not a broad wipe, not the imprecise version that Lockhart had used and which had destroyed a mind rather than editing one. The surgical version, keyed to specific memories rather than time windows. He had been practicing this since June with the specific patience of someone who had identified a skill that mattered and intended to have it before he needed it.
He practiced the counter-curses for the spells he knew would be on the treasure and had practiced other ones that he would find useful
He walked through the Leaky Cauldron and into Diagon Alley and moved through the morning crowd toward the white marble building at the far end.
He was Ron Weasley, age fifteen, going to his vault.
He climbed the steps.