Package Manager Errors - dev package dependencies

I have been developing a few packages all in the dev directory. Some are dependent on others. PkgA has Pkg C in it’s dependencies. PkgC has PkgB in it’s dependencies. Currently to precompile PkgA, I need to do the following:

julia> using PkgB
[ Info: Precompiling PkgB [xxx-xxx...]

julia> using PkgA
[ Info: Precompiling PkgA [xxx-xxxx...]
┌ Warning: Package PkgA does not have PkgB in its dependencies:
│ - If you have PkgA checked out for development and have
│   added PkgB as a dependency but haven't updated your primary
│   environment's manifest file, try `Pkg.resolve()`.
│ - Otherwise you may need to report an issue with PkgA
└ Loading PkgB into PkgA from project dependency, future warnings for PkgA are suppressed.
workdirectory = "D:\\Gdata"

Now I am trying to get PkgB into PkgA’s dependencies to eliminate the warning message. But I get this error:

(PkgA) pkg> add PkgB
ERROR: The following package names could not be resolved:
 * PkgB (not found in project, manifest or registry)

(PkgA) pkg> add C:\\Users\\dkzwa\\.julia\\dev\\PkgB
    Updating git-repo `C:\Users\dkzwa\.julia\dev\PkgB`
   Resolving package versions...
ERROR: expected package `PkgC [xxx...]` to be registered

Now there is another (registered) package I want to put into PkgA’s dependencies, LibPQ. When I try, I get another error, which I suspect is related:

(PkgA) pkg> add LibPQ
   Resolving package versions...
ERROR: expected package `PkgC [xxx...]` to be registered

I don’t think I am doing anything differently than when I added PkgB to PkgC. Any idea if I could be doing something wrong or if there is an issue with the package manager?