deprecateAt

The date and time to deprecate the AMI, in UTC, in the following format: YYYY-MM-DDTHH:MM:SSZ. If you specify a value for seconds, Amazon EC2 rounds the seconds to the nearest minute.

You can’t specify a date in the past. The upper limit for DeprecateAt is 10 years from now, except for public AMIs, where the upper limit is 2 years from the creation date.