Google shows that the drive from Fulton to Service Campground at Coffeeville, AL on the Tombigbee River, is 20 miles further but 20 minutes shorter by backtracking a few miles into Tupelo and taking US45/Alt45 to Coffeeville. About 232 miles.
From Coffeeville to Ft Pickens is only 150+ miles and less than three hours. Not sure why you want to throw an extra stop in there.
I guess they got the road back in service into Ft Pickens, as the closing alerts have been removed from the NPS.gov and recreation.gov websites. They are soliciting for bids for a ferry service, I suppose as a backup.
If you only want to do one night on the road, the exact half way point would be Persimmon Hill Rec Area on Enid Lake off of I-55, exit 233. I used Chesterfield mall as a starting point and this is 360 miles from there, and 360 more to Ft Pickens.
https://www.recreation.gov/camping/persimmon-hillenid-lake/r/campgroundDetails.do?contractCode=NRSO&...This is in NW Mississippi between Batesville and Grenada.
My tolerance is 500 miles a day give or take a few, and this worked well for me on my trip out to the Black Hills. Only issue is in Feb you don't have the daylight as long and it could be getting dark by the time you make the campsite.
If you are willing to spend a second night on the road, but want to be closer to FL, is the Magnolia Branch Wildlife Reserve and Campground. operated by the Creek Indian Tribe, it is located off of State 113 a few miles south of the exit 69 interchange on I-65.
http://www.magnoliabranch.com/https://goo.gl/maps/W3JQscebUaqBear in mind, I have never been to either of these campgrounds, but may consider the one at Magnolia Branch sometime.
Charles
'03 Ram 2500 CTD, 5.9HO six speed, PacBrake Exh Brake, std cab, long bed, Leer top and 2008 Bigfoot 25B21RB.. previously (both gone) 2008 Thor/Dutchman Freedom Spirit 180 & 2007 Winnebago View 23H Motorhome.