You need to write to the source directory metadata that the file is no longer there, then write to the destination directory metadata that the file is there.
I wrote down my guesswork here. Assuming an upload failed due to lost race, but still fast enough to be moved to blobs directory, we’d skip the database update and the orders file update—both are not synced, so they are likely coalesced along multiple uploads.
And I do, because numbers say so. 1.5h is non-trivial. 3 additional seeks on top of (best case) 10 seeks is 30% more.