If you have just made a purchase of an AIT Hosting plan, you will notice that your Account will have a two charges on it: one for the cost of the server and one for a smaller amount.
The first charge is a pre-authorization charge, which ensures the credit card is valid and able to be charged. This initial charge will be refunded within 10 business days.
The second charge is the pro-rated cost of the server. This number will vary depending on the date you placed the order and the next billing cycle. For example, even if the price of your server is 100 dollars, if you order the server near the end of the month you will only be charged around 10 dollars for that first month.
Please bear in mind, if you order your server on the 29th, and you are billed for the pro-rated amount when it is processed, then on the 1st of the following month you will be billed again for the full amount.