SkySilk VPS plans are billed at their listed monthly rate on the 1st of each month, and account for 28 days (or 672 Hours) of total possible uptime. Uptime is defined as any VPS that is deployed (On or Off), and will be counted towards your monthly invoice for the total time deployed, up to a total of 672 hours per month.
Transfer overages for Basic and Standard VPS plans are billed at a rate of $0.10/GB per month. Premium VPS plans come with Unlimited Transfer and do not incur overage fees.