Recent experience: I was on a 772 this past Friday. 2 days before, on Flightstats, it showed a tail number with zodiac seats. However, the seat map never updated to show the reverse facing seats. The morning of the flight, the tail number changed to a 772 with all forward facing.

Bottom line, you really won’t know for sure until the morning of your flight. And as someone posted above, it can change based on a mechanical or a late arriving flight.