Here is what I have about Edmond & Jane (Roche) Brannock.
The first record of a Brannock in Dorchester County appears in Pat. L17, F76, which shows that Edmond Brannock immigrated with his wife, Jane, in 1666.Jane was probably the daughter of Alexander Roche since she was named in his will (Wills 1, 619).(A popular rumor is that they came from Scotland but I really don't know if that is true.
Edmond and Jane had the following children:Thomas, David, Edmond, John, Mary, Elizabeth, and Jane Jones.Edmond Brannock made a will dated September 1, 1701, and it was probated January 5, 1703 (Wills 3, 18).
David Brannock, son of immigrant Edmond Brannock, was living in South Carolina by 1734 (DLR 9 OLD 256).(Now this could be the link you are looking for)
It appears that the other 3 sons remained in Dorchester Co., Md.John had no sons.Thomas had 5 sons - Edmond, John, Philemon, Henry, & William. Edmond had 1 son - Thomas, who moved to Delaware sometime after 1742.
This information was obtained from FIRST DORCHESTER FAMILIES by Calvin Mowbray.
Now the names William and Henry Brannock are (or were) very common in Dorchester County, so it is possible that you are on the right tract by looking for your ancestors in Maryland.I have heard that by the mid 1800s, many of them had moved to NC and KY.
I also checked Brannock marraige records and could not find the name Wright referenced anywhere in Dorchester County.