The Premier service is a service pack including:
The first year of Premier service is included with new licenses.
Then the Premier service is optional but highly recommended. It is available on an annual subscription basis.
The Premier service renewal must be purchased before the previous Premier service expires to get the lowest price (about 20% of the original license price for Webots PRO & Webots EDU, 100% of the original price for Webots MOD). Moreover, this ensures that you won't experience any interruption with user support and upgrades. If you don't renew your Premier service within 12 months, you can still renew it at any time for a more expensive price (price increases as time passes).