Please use this link for upgrading your commercial license.
You will only have to enter your license number which you will find on your commercial license and enter the amount of the difference.
For example, for upgrading a Standard commercial license at $49 to a Desktop + Webfont license at $89, you will have to pay the difference which is $40.
If any doubt, please contact me.
You can pay by Paypal or by credit card. The payment is secured by Paypal in all cases.
You will receive the updated commercial license within 24h at your email provided during the payment or your Paypal email.
Please note that it is not an automatic process, I will personally send you the commercial license by email, therefore there may be a little delay sometimes.