VIP Service is a cloud-based solution which is charged on monthly or annual subscription basis. One VIP account (including up to 5 credential IDs) is charged at $3.00/month, but if you buy with annual subscription model, one VIP account is charged with $30.00/year (instead of $36.00).
Take an example of 50 resellers under you. Regardless of how many your servers are running WHM/cPanel, you just buy 50 X 3$ = 150$ for your resellers to use the VIP for one month, just to cover the number of resellers you are handling. If you want to enable annual subscription for your 50 resellers, then you just buy 50X30$ = 1500$ instead of repurchasing every month. Basically, it is a shift from traditional per-server license type toward per-users / per-credentials subscription license type .