What will happen if visitors exceeded the limit number?
What happens when the 50k monthly visitor limit is reached in a free account? Are all running tests paused until the end of the month? Do visitors (new and returning) still see test variations?
Yes that's correct, your experiments will be paused until the end of the month (or more precisely, until the date in the month that you opened your subscription - we call it the beginning of the next 'billing cycle').
Because your experiments are paused, they are not running so they will see your original site.
We exceeded the user limit in the period, but even after starting a new cycle my limit not renewed. What should I do to be able to renew the 50k limit users? My start day was Saturday, March 5, 2016 and today is april 6.