So, this is what we know so far…?:

Disney buys LucasFilm in October 2012.
Reliance scans the OT ('97 SEs) in 4k, presumably starting in 2012, finishes around 2014.
Gareth Edwards watches a “recently finished” 4k version of ANH in 2014.
Rumors ahoy!

The scans being done in 2012 makes perfect sense. Disney would definitely want something better than the awful 10-bit 1080p telecines that were used for the Blu-rays - they were outdated by the time they were even finished! Even if it’s not the OOT, we will still have much better material to work with.