The current version of the list (now availble in the Vault) doesn’t appear to require that many changes. One possible change is the modification of the Power Field Big Mek upgrade to be 1D3 Power FIelds instead of 1.
There are two areas that might have a possible impact on the list. Tom, the Fanatic production manager, has begun to look at the army list in oder to determine what figures and “bitz” they can produce. So there may need to be units removed or reworked to fit into the production schedule that Fanatic has.
The second biggest possible impact is the current changes to the barrage table and MW barrages in the latest experimental rules that Jervis has posted. Since the OGBM list can be outfitted with a large number of MW and MW barrage weapons this change may effect the balance of the army list.