All subscription plans are prorated daily based on the number of Matter-connected channel users.
The invoice amount will be automatically adjusted and charged at the end of the billing cycle to the payment method on file. A decrease in channel users will result in a credit towards the next invoice amount.
In other words, you'll only pay based on the number of channel users and how long they are in the Matter-connected Slack/Teams channel.
Note: Enterprise Grid billing is the unique aggregate number of channel users across all Matter-connected channels.
For annual subscriptions that have an increase in channel users (i.e., an increase in cost), the prorated adjustment will be billed 30 days from the channel user increase or the next month after the last charge - whichever date comes earlier. Whereas monthly subscriptions will keep the same billing cycle.
For example, if you upgrade on January 1st and add 10 users on July 1st (6 months into the year), you'll be billed for those 10 users on August 1st for the billing period of July 1st - December 31st.
Vice-versa, if you remove 10 users on July 1st, you'll receive a prorated credit for the 10 users for the 6 months of unused time on your next invoice on January 1st.