New accounts default to long EC2 resource IDs on March 7
In January, Amazon Web Services announced the availability of longer IDs for EC2 instances and reservations. As of March 7, 2016, newly created AWS accounts will use longer EC2 instance and reservation IDs by default in the following regions: US East (Northern Virginia), US West (Oregon), US West (Northern California), EU (Ireland), and EU (Frankfurt). In other regions, new accounts will use longer EC2 instance and reservation IDs by default starting in mid-April 2016.
If you create a new AWS account on or after March 7, 2016, your new account will receive longer EC2 instance and reservation IDs by default in the regions noted above. We recommend testing longer IDs before transitioning; however, if you have not yet tested your systems for compatibility with the longer format, you still have the option to opt out and receive shorter IDs until early December 2016. Longer EBS volume and snapshot IDs will be available in April.
For more details, and for instructions on how to adjust your ID format settings, visit the AWS Blog, the EC2 FAQ, and the EC2 User Guide. If you have questions, contact the AWS support team.