They don't use the
prefix PH, just those letters in the reggie eg. VT-PHA.
And you are right about the British Empire, VA through VZ were assigned to British Overseas Possessions in 1923(?). Hence Australia (VH) and India (VT) and all those little colomies in the VP, VQ and VR ranges. VR was reassigned to China in 1997, but they have never used it. VC is still allocated for Canada but only used in military callsigns and that practice was discontinued decades ago.
Viceroy's Territory is pure nonsense.
(A link to the full International Radio list was posted in an earlier thread about reggies, but I can't be bothered to search
)