The white and grey are slated for a June release.
I did notice the slight changes, but only the way they lace and the strap length. They've actually adjusted the strap length on the red ones as well.
The funny thing about the black/red ones is Nat from Hookgrip did a mock up of a shoe he'd like to see after the white and grey ones were announced. IIRC these look very similar to his idea.