So there is usually one more step, why not phone VS Gold helpline and 'play innocent' by asking what incentive you have to stay with them during your current membership year.
The answer is likely to be '......more miles at Gold bonus rates, sir...'
A Centurion card is, as Paxboy says, an invitation because it costs to own it. The next "level" at Virgin is 'bestowed' upon you because you are providing revenue of about £40-50k per annum.
Still, might be worth a shot...
