Renewal of SEP 12.1-reg

Sir

I am having 110  Licences of SEP 12.1  WHICH IS DUE FOR EXPIRY  on 26-02-16.Is there any grace period for  Renewal? If so,how many days?

Will the Clients receive updates ater Expiry?

After Expiry  of grace period, is it possible  to renew the Licences or i have to purchase fresh?

Please guide me.