What does Create all high do, and is anything posted automatically?

Create all high — review before posting lists every high-confidence suggestion with the exact Xero entry it will make. Certified ones, and those matched to a document, start ticked; the others say why they are not. Untick anything you are not sure of. Nothing is sent until you press Create; each entry is then posted one after another and reported. Confirming the bank line stays in Xero. Whether the list holds only certified suggestions or every high-confidence one is the “Create all high” includes setting on Accounts → Settings → Bank Recon (certified only unless your account changed it).