If you want to upgrade your active plan to a higher version of Xen Orchestra, you can do it from your personal space at https://account.vates.fr
Pick the line corresponding to the account you want to upgrade. Click on the "upgrade" button on the right. At this point, you will see a standard subscription page. Choose the same payment method you used to purchase the initial plan and confirm the purchase.
If you choose wire transfer, you have now the possibility to download a quote. As you can see, the remaining period of your previous plan is now a credit note applied on this upgrade.
As for a regular purchase, upload a proof of payment in order for us to activate your new plan as soon as possible.