SeatExpert
I did look at the DL SeatMaps, which seems to indicate a normal domestic aircraft.
However, if one types in those flight numbers and dates on SeatExpert.com, it gives the information for both the domestic and the int'l 67-3, indicating that either aircraft may be used ...
Was just trying to figure out the frequency of this ... and it looks like it's an infrequent and lucky happening ...