You can switch between monthly and yearly billing from your Plan page. Click the 'Manage Your Subscription' button to open your subscription settings. Click Update Plan to see the options.
Yearly billing offers 2 months free ($50/year instead of $60/year).
If you switch from monthly to yearly billing the amount you pay will be pro-rated by the amount of days passed in the current month.
There are no feature differences between monthly and yearly billing, just the 2 months discount.
