Support cost is a prorated value based on 40% of the initial cost. Consider the following example:
Original purchase date
Number of copies
January 01, 2010
June 30, 2010
Total cost of renewal on January 01, 2011
In the example above, you have purchased 4 machines licenses for Syncrify. The support contract for all four of them ends on January 01, 2011. Since you purchased the later two copies just six months ago, you owe half the amount.