The names you mention are actually in the will of Leonard Adcock of Granville co 1780 according to published transcripts. I too wondered about Josebad being Joshua. However, Josebad is said to be female.
There is a John Adcock Sr in later tax lists who is possibly the John of Leonard/Johns will of 1780. In which case this could be the John Adcock who is said to be father of Joshua of Chatham (land grant for Revolutionary War Service) and Captain Leonard of Tennessee who was in SC in a census or two, but moved to Western NC, what would become Tennesee similary with a post war land grant.
I expect to go to the archives this month and I will certainly search down the 1780 will and see if it is Leonard or John and check the spellling of "Josebad" etc.
It appears to me that John Sr. of Granville Co NC, is a generation later than the "Old" John of VA that some claim.