I suspect that the number of transfers from SPG to a given airline in a two- or four-week period is probably small enough to fit on an Excel spreadsheet. I wouldn't be surprised at all if it was sent as an attachment to an email, and each transfer was either manually entered into a computer system, or they had some script that would scrub the FFP numbers, names, etc., from the spreadsheet and import them into their system. Not all are like this; for example, transfers from Chase UR to airlines are realtime and immediate, in my experience.