Prior to in1984 VR was Brunei - changed upon the resumption of full independence to V8- to align with the radio call sign, not for anti-colonial reasons. India's VT was randomly assigned, like most registration letters, in the V series used in some cases for former British colonies. Other territories formerly ruled by the British use other codes however - in the S and Z series for example so the VT code doesn't really have any particularly colonial significance. For example, I don't recall Vietnam (VN) ever being ruled by a British Viceroy and of course there's that other large former British colonial territory that uses the registration letter N.
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Through difficulties to the cinema