no, yes and yes -- but I am just a dumb passenger, don't have any industry knowledge. However pretty sure this is correct, the date on the ticket is absolute -- no matter if it is right or wrong. And similarly for the revalidation sticker, once you have it, its done. The flying airline does not care as it will be paid by the clearing house, no matter what (the issuing airline has all of the risk. And having a confirmed reservation is irrelevant, it is the ticket that counts.