LEIs can be renewed up to 60 days before they expire.
If you use RapidLEI as your LEI Issuer, log in to your account and your LEI Management dashboard will show you which LEIs to renew before they lapse.
If you are not a RapidLEI client, you will first need to transfer your LEI to RapidLEI management.
Do not worry about losing remaining time on your LEI when renewing early. Remaining time is added to the next expiry date.
More info: Renew LEI