When you renew your account, no matter whether you renew it exactly on its expiration date or a few days/weeks/months earlier, the renewal will count from the account’s expiration date.
For example, if your account expires on the 17th of May 2020 and you renew it for 1 year on the 11th of May 2020, then the new expiration date will be 17th of May 2021, not 11th of May 2021.