Not sure why they changed the handguards but here's some info.
The handguards are marked USA and HGW1 or HGW2 in the rear portion. The heat shield is one piece Aluminum(?) and is anodized Black/ Purple Black and has heat venting holes on the sides just to the right and left of where the top holes should be.
Where top hole on the handguards are is covered by a solid piece of metal. The handguards appear to be made out of the same material as the New M4 6 position stock.
Everyone of the carbine uppers I've order in the last month/month 1/2 have come with this new handguard