What is a Platinum customer?

I called Vodacom on the 3rd January at 19:12 to find out what the rules are around being a platinum customer which allows upgrades to be more frequent. I was told that someone would call me but it never happened, I received an SMS at 19:27 on the same day that read "Your number is not yet qualifying to a platinum memeber Regards Vodacom". Apart from the shocking grammar and spelling from a large corporate, it still did not answer my question. I called back at 19:29 and was assured that someone would contact me, but that has still not happened. I spend over R7000 a month on my overall profile, and my invoice amount on my personal number is around R2600 .... what are the rules?