If you are choosing a monthly subscription, you will be able to upgrade, downgrade, change the number of users or operators at any point through the admin section in your system. If you wish to cancel a subscription Manu online will require at least 1 month notice prior to the cancellation date.
If you are using an annual subscription, again you would be able to upgrade, downgrade, change the number of users or operators at any point through the admin console. This will not affect your current agreement and you will not enter into a new annual agreement.
In both cases you account will stay active until the subscription period ends.