After the release of the Service Pack 1B for the PMDG 777-200 earlier this year, PMDG have been working on the next update which is SP1C.
In a post on AVSIM they annouced that it will be released in the next couple of days. They also said “we are doing some integration testing” and they are also working the iron out some issues they are having with it. They did have the intention of bringing the update out for this weekend but that sadly didn’t happen. All we know is that they are working to create a product that is of a high quality.
You can see the full forum post here