Extra airmiles with more BMI credit cards!

I got my BMI card through last night. I had actually been told by a friend that if you get the normal card and then upgrade to a platinum card at a later date you can get another 20,000 miles. I wanted to wait to get my first card before I called and asked them about this offer but the card they sent me was a platinum card. So I called and asked anyway as this meant that I definitely wouldn't get another 20,000 miles. But they told me that upgrading to a platinum after you've already received 20,000 miles will not get you any more.

BUT...

She told me that you can hold up to five credit cards from them at the same time and they'll give you 20,000 miles for each of them. I was very surprised by this so I would like more confirmation first but it seems that you could then get up to 100,000 free miles. The only problem is that you can't combine them. But you could use them for five single journeys. That could get you to zone 5 and back for free or by paying a supplement you could get any zone apart from 9 with two lots of 20,000 miles. So two credit cards could get you a whole lot further. Unfortunately the cost of airmiles from other zones to other zones is quite high and very limited but I'm sure the table was intended for UK users. So in theory you could potentially get five credit cards and plan yourself a round the world trip. It would still probably cost quite a bit though.

http://www.flybmi.com/bmi/src/html/diamondclubhowtospendmiles.html