Mark,TCM had a Film Festival touting the restoration back in 2015. Here's the only documentation I could still find on that:
In December of 2015 iTunes rebranded the version that they sell with new iTunes extras and new artwork. I'll admit I can't find any documentation to prove that the actual movie file was replaced with the restored version, but I always assumed that it was.
Edit: Actually there was a discussion about the Restoration in this very forum. Here is a post saying that a Fathom event advertised that the iTunes file was being upgraded:
Yesterday, I was going back and forth between Vudu and iTunes regarding Roman Holiday. When I pulled up iTunes I noted a 2007 date attached to iTunes extra movie file. That date confused me. By the way, the iTunes purchase price was $14.99 while Vudu was charging $6.99 as their purchase price.