matt@Wallace:~$ apt list gdm3
Listing... Done
gdm3/bionic-updates,bionic-security,now 3.28.2-0ubuntu1.4 amd64 [installed]
N: There is 1 additional version. Please use the '-a' switch to see it
matt@Wallace:~$ apt list gdm3 -a
Listing... Done
gdm3/bionic-updates,bionic-security,now 3.28.2-0ubuntu1.4 amd64 [installed]
gdm3/bionic 3.28.0-0ubuntu1 amd64
gdm3 info. for above comment
matt@Wallace:~$ apt list gdm3 updates, bionic- security, now 3.28.2-0ubuntu1.4 amd64 [installed] updates, bionic- security, now 3.28.2-0ubuntu1.4 amd64 [installed]
Listing... Done
gdm3/bionic-
N: There is 1 additional version. Please use the '-a' switch to see it
matt@Wallace:~$ apt list gdm3 -a
Listing... Done
gdm3/bionic-
gdm3/bionic 3.28.0-0ubuntu1 amd64