It’s important to remember that when an ArcaOS 5.0 license is to be upgraded, and it has a Support & Maintenance subscription in effect, several actions take place automatically on Arca Noae’s side of the transaction and other actions should take place on the customer’s side.
First, on the Arca Noae side:
- The existing ArcaOS 5.0 Support & Maintenance subscription for that license is terminated as of the date of the upgrade of its associated license to ArcaOS 5.1.
- With the termination of the ArcaOS 5.0 Support & Maintenance, access to associated downloads for ArcaOS 5.0 is removed If you have more than one ArcaOS 5.0 license with current support and are only upgrading one of those licenses to 5.1, the associated downloads will still be available for your other ArcaOS 5.0 licenses.
- Whatever time was left on the ArcaOS 5.0 Support & Maintenance subscription is added to the included subscription for ArcaOS 5.1. (So, if you recently renewed your 5.0 subscription, and it had 12 months before the next renewal, your new ArcaOS 5.1 personal license will now have 18 months of support & updates.)
On the customer side, the installation of the ArcaOS 5.0 license being upgraded should be upgraded to ArcaOS 5.1. It is a violation of our license terms to upgrade a 5.0 license to 5.1, install the 5.1 license on another system or partition, and to continue using the 5.0 installation. One license is consumed per bootable installation, regardless of the edition (personal or commercial). If that license has been upgraded, the upgraded license is only valid for the upgraded ArcaOS version.
If you would like to maintain access to ArcaOS 5.0 downloadable content, but would also like to install ArcaOS 5.1, then we invite you to purchase a new ArcaOS 5.1 license from our store or from your preferred authorized reseller. In that case, the two subscriptions will be separate, and their contents will be available in your ArcaOS Download Center as long as the respective subscription remains in force.
For more information, please refer to this FAQ item.
Source: https://www.arcanoae.com/clearing-up-some-more-upgrade-confusion-subscription-downloads/