A new release of the Ubuntu Cloud Images for stable Ubuntu release 21.04 (Hirsute Hippo) is available at [1]. These new images superseded the existing images [2]. Images are available for download or immediate use on EC2 via publish AMI ids. Users who wish to update their existing installations can do so with:
   'sudo apt-get update && sudo apt-get dist-upgrade && sudo reboot'.

The following packages have been updated. Please see the full changelogs
for a complete listing of changes:
 * linux-meta: 5.11.0.25.27 => 5.11.0.31.33 
 * linux-signed: 5.11.0-25.27 => 5.11.0-31.33 


The following is a complete changelog for this image.
new: {'linux-modules-5.11.0-31-generic': '5.11.0-31.33', 'linux-headers-5.11.0-31': '5.11.0-31.33', 'linux-headers-5.11.0-31-generic': '5.11.0-31.33'}
removed: {'linux-headers-5.11.0-25': '5.11.0-25.27', 'linux-headers-5.11.0-25-generic': '5.11.0-25.27', 'linux-modules-5.11.0-25-generic': '5.11.0-25.27'}
changed: ['linux-headers-generic', 'linux-headers-virtual', 'linux-image-5.11.0-31-generic', 'linux-image-virtual', 'linux-virtual']
new snaps: {}
removed snaps: {}
changed snaps: []
==== linux-meta: 5.11.0.25.27 => 5.11.0.31.33 ====
====     linux-headers-generic linux-headers-virtual linux-image-virtual linux-virtual
  * Bump ABI 5.11.0-31
  * Bump ABI 5.11.0-26
  * Packaging resync (LP: #1786013)
    - [Packaging] resync debian/dkms-versions from main package
==== linux-signed: 5.11.0-25.27 => 5.11.0-31.33 ====
====     linux-image-5.11.0-31-generic
  * Master version: 5.11.0-31.33
  * Master version: 5.11.0-26.28

--
[1] http://cloud-images.ubuntu.com/releases/hirsute/release-20210817/
[2] http://cloud-images.ubuntu.com/releases/hirsute/release-20210816/