Originally Posted by N515CR

Since dl.com isn't accurately showing the flatbed icon on some of these flights, per a post on a.net:
"The only way to make sure is by the seatmap. The new 75S configuration will have Economy Comfort rows extended to row 25 (whereas the old 75E config had EC only up to row 22). Also, the 75S does not have seats 35ABC whereas the 75E does."

Based on this, N624AG, N718TW, and N721TW have the new seats. N723TW is supposed to be the 4th.