Open Services in HostVyx, select the service, and choose Upgrade/Downgrade.
Upgrades
For a monthly hosting upgrade, HostVyx calculates the difference between the old and new package. The current-month adjustment covers the upgrade date through month-end. If the change is made on or after the 25th, the following full month difference is included as well.
Downgrades
A downgrade is handled as a credit or future billing adjustment rather than an unexpected immediate charge. Review the confirmation screen before approving the change.
After approval
The service package and next billing date are updated after the change is accepted. Keep the confirmation for your records and contact support if the displayed adjustment does not match your expectation.