The auto-upgrade feature allows your team to grow as the number of team members using the product increases. Only Billing Admins and Account Owners have control over this function. With auto-upgrade turned off, your users will receive a notification within the product that you have reached your license allocation. Enabling auto-upgrade allows your team to grow as new members join and disables the in product notification.
This setting can be changed by going to your Subscription Level tab within your Account Settings.
When your team reaches the maximum amount of allocated licenses for your current team size, Lucidchart will automatically upgrade the account to the next team level. For example, if you are currently on a Team 3, your team will upgrade to a Team 5. If you are currently on a Team 5, your team will upgrade to a Team 10. After that, each additional upgrade will add ten licenses to the team.