Something to look out for with the VS Amex card

Received my Black VS Amex statement today and noticed that I had not earned any bonus miles for pre-ordering VS retail therapy using the card.
I had also made an in-flight purchase with the card , which did earn the bonus (x4) miles.
Spoke to MBNA who said this is correct. They say only in-flight purchases earn the bonus miles.
The odd thing is though both on-board and pre-order have the same MCC (merchant category code - 5309) although the merchant text is different?
Anyone else had this happen? Are MBNA correct?
Looking at the VS website, that's a bit vague:
I had also made an in-flight purchase with the card , which did earn the bonus (x4) miles.
Spoke to MBNA who said this is correct. They say only in-flight purchases earn the bonus miles.
The odd thing is though both on-board and pre-order have the same MCC (merchant category code - 5309) although the merchant text is different?
23/09/2010 5309 VIRGIN ATLANTIC INFLIG GATWICK AIRPO
06/10/2010 5309 TOURVEST DUTY FREE GATWICK
Anyone else had this happen? Are MBNA correct?
Looking at the VS website, that's a bit vague:
Earn double miles on Retail Therapy purchases when you pay using your Virgin Atlantic Credit Card.
That's 2 miles for every £1 spent on the White Card, and 4 miles for every £1 spend on the Black Card!