To change or upgrade your plan, go to the user icon in the top right corner, then click Manage Organization. Click on Manage Plan. If you just want to change your billing cycle from monthly to yearly or vice versa, select “Change billing cycle to ____.” Review the terms of your new plan, then select Confirm Change. 

However if you want to change the plan you are on, click Change Plan on the Manage Plan page, and then select the plan that you wish to switch to. On the next page, review the details of your new plan, then select Confirm Plan. 

Note: You can only change or upgrade plans on the web version.