I have not heard anything. 310.15(B)(6) allows 400 KCMIL THWN copper for a 400 amp dwelling service. You could go traditional and use 500 KCMIL THWN, both fit in 2 1/2 per Annex C - Table C1 EMT and C4 IMC. In table C8 for RMC, 500 KCMIL would have to be in 3 inch.
Re: New 3" hub code for Resi Load Centers??#48388 02/10/0510:00 PM02/10/0510:00 PM