The new 00Z EC-AIFS has become more aggressive with the cyclone.
At F78, 06Z Saturday Sep. 26, it's down to about 989 mb. Compare that with the 18Z AIFS at roughly the same point, which was around 997 to 988 mb depending on the exact six-hour frame. More importantly, look at the position: the 00Z AIFS still has the center much farther west than the 00Z GFS, sitting roughly east of the Delmarva/NJ corridor rather than racing harmlessly toward the open Atlantic.
And look at the structure. The isobars are extremely tightly packed on the western and northwestern side, right toward the Mid-Atlantic and southern New England. That's a very substantial pressure gradient between the cyclone and the 1026 mb high to the north.
The deepening sequence on this 00Z AIFS is also worth watching. We had approximately 999 mb at F54, and now 989 mb at F78. That's 10 mb in 24 hours, so this particular 24-hour interval is not bombogenesis. But the cyclone is already quite deep by Saturday morning, and what happens during the next 12 to 24 hours is the fascinating part.