On your credit card statement it will show how many flight points you have, and how many of transferred - the amount transferred will match your spend points. If you spend $100 on groceries, that will amount to 200 spend points and if you have earned flight points then 400 will get transferred. If you don't have enough flight points then your spend points will be transferred, but when you earn flight points in the future you will get those 200 that were owed to you transferred. So the flight points do not have to be there when you have spend points.