The Mountains-to-Sea Trail is an 1175-mile route running across North Carolina, from Clingmans Dome in the Great Smokies to Jockey’s Ridge on the Outer Banks. About 700 miles of the route are on natural surface footpath, unpaved forest roads, greenways or beaches. The remaining miles are on connecting back roads. In 2015, a new route was established in the southeast, through the Coastal Crescent portion of the state, increasing the overall mileage from 900 miles to 1175. This route includes more public lands, ripe for trail building, and more communities to support long distance hikers. The historic route that previous FKT records prior to 2015 were set on has been retired and is no longer used by hikers. An alternate paddle route was also added on the Neuse River, which shortens the overall length of the trail to 1010 for those completers who chose to paddle. Each year, approximately 15 new miles of trail are added, and road miles reduced. For more information, go to www.mountainstoseatrail.org
The following two efforts used the 900 mile route:
Matt Kirk ran & hiked the trail in 24d3h50m on July 1-24, 2011. Kirk's trip was basically thru-hiker style, which we consider to be in the "self-supported" category, but apparently he did have some help from family in the second half (see below). His trip report is Matt's blog here. During the trip a website was set up to report on his progress. It includes links to articles, maps and photos.
Kirk has these things to say:
I wish to inspire people of all ages to break free of the self-destructive habit of driving everywhere and get out and use their original God-given vessels, their bodies, for transportation. There are a million excuses, and some of them are fairly legitimate, for remaining encapsulated inside a car. But the benefits of walking, running and biking are undeniable. And,
I like to hike.
Diane Van Deren tackled the MST in May-June 2012 as a fully supported, ultrarunning style adventure, sponsored by The North Face. She completed the route in 22d5h3m, on June 1, 2012. An article on her run from the Charlotte Observer is here.
Note that the MST is an evolving trail. Each year road sections are replaced by trail, and according to the MST website "The current  route of the MST includes 680 miles of trail and about 500 miles of connecting roads. Our goal is a continuous off-road trail across North Carolina, and each year, as new trail opens, Friends adjusts the current route to incorporate that new trail. Over the last ten years, an average of 15 new miles of trail have opened each year. We expect that this rate of change is likely to continue in the foreseeable future." Therefore, the route is almost certainly has gotten "slower" over time.
"Pitchell" is a challenge dreamed up by Ashville, NC, runner Adam Hill, which is run on (mainly) a section of the MST, 67 miles from the top of Mt Pisgah to the summit of Mt Mitchell. See link for FKTs.