Omega 4 RC1 -> Omega 4.0 body classes change

I updated a site from 4 RC1 -> 4.0 and noticed a lot of my layout CSS was breaking where I had used layout specific body classes (sidebar-first, no-sidebars etc..). I found the changes where the classes like 'sidebar-first' are pulled from , however couldn't get a preprocess in the subtheme to work to add them back in. I also didn't have the new classes (that OHM has) for sidebars. had no layout specific classes, including the new ohm 'has-x-sidebars'.

Does anyone have any ideas how to get these classes back in (in the sub-theme)? I've got about 4 sites to update with this preprocess function.

My findings so far: html.preprocess.inc in Omega removes the classes on line 55. Then template.php should add the new (by new I mean different) sidebar classes in the _omega_preprocess_default_layout_variables function on line 750 but didn't work for me.

Adding this function in the subtheme didn't work either (to get the RC1 classes back).

Any help is much appreciated!