How far Prince Philip might have risen in the Royal Navy

How high might the Duke of Edinburgh have risen if King George VI had lived longer and allowed him a normal naval career?

Promotion into the admiral ranks is plausible, with the service's highest leadership a possible upper limit in that counterfactual.

Continuing a normal naval career could have taken Prince Philip well into the admiral ranks. Reaching the service's highest leadership is also raised as a possibility. That upper limit remains speculative and depends on the longer reign of George VI envisaged in the question.