apt-get update fails on Kali KEYEXPIRED

if

apt-get update

fails on Kali 

with an error like this

Get:1 http://kali.download/kali kali-rolling InRelease [30.5 kB]

Err:1 http://kali.download/kali kali-rolling InRelease

  The following signatures were invalid: KEYEXPIRED 1517583136  KEYEXPIRED 1517583136  KEYEXPIRED 1517583136  KEYEXPIRED 1517583136  KEYEXPIRED 1517583136

Fetched 30.5 kB in 8s (3,483 B/s)

Reading package lists... Done

W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://kali.download/kali kali-rolling InRelease: The following signatures were invalid: KEYEXPIRED 1517583136  KEYEXPIRED 1517583136  KEYEXPIRED 1517583136  KEYEXPIRED 1517583136  KEYEXPIRED 1517583136

W: Failed to fetch http://http.kali.org/kali/dists/kali-rolling/InRelease  The following signatures were invalid: KEYEXPIRED 1517583136  KEYEXPIRED 1517583136  KEYEXPIRED 1517583136  KEYEXPIRED 1517583136  KEYEXPIRED 1517583136

W: Some index files failed to download. They have been ignored, or old ones used instead.

The fix appears to be these 2 commands that get new keys

wget https://http.kali.org/kali/pool/main/k/kali-archive-keyring/kali-archive-keyring_2018.1_all.deb

apt install ./kali-archive-keyring_2018.1_all.deb