One of those RMW employees' resumé's said they were working on this as early as 2010. I'm not gonna go back into this massive thread and find it, but the wording was definitely that they'd "completed" a 4k restoration on the trilogy by then (didn't say which version, though). This means they would've started work on it even earlier. If those dates were accurate, the question remains as to why this newer transfer wasn't used for the 2011 blu-ray. Maybe George really didn't want to spend a dime on making everything perfect and "final" for the 3D conversions until he absolutely had to, so the 2004 masters were recycled since they're at least technically 1080p and those 2011 changes were done as cheaply as possible. As Zombie said, the 3D re-release of ANH was still years away at that point.