Unable to update GitLab CE from 13.4.3 to 13.5.4 - gitlab-ce

Question

I've a Ubuntu Server 20.04.01 LTS machine with a GitLab CE (v13.4.3) installed less than a year ago.
I'm not able to update to the new 13.5.4 version because apt tell me that all packages are up to date.
ebenedos#fcssrv-git:~$ sudo apt-get update && sudo apt-get install gitlab-ce
Hit:1 http://it.archive.ubuntu.com/ubuntu focal InRelease
Hit:2 http://it.archive.ubuntu.com/ubuntu focal-updates InRelease
Hit:3 http://it.archive.ubuntu.com/ubuntu focal-backports InRelease
Hit:4 http://it.archive.ubuntu.com/ubuntu focal-security InRelease
Reading package lists... Done
Reading package lists... Done
Building dependency tree
Reading state information... Done
gitlab-ce is already the newest version (13.4.3-ce.0).
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
I've also tried to check for missing migrations but seems that it's all ok
ebenedos#fcssrv-git:~$ sudo gitlab-rails runner -e production 'puts Gitlab::BackgroundMigration.remaining'
0
Also tried to force the update to an updated bugfix version before updating to 13.5.4
ebenedos#fcssrv-git:~$ sudo apt-get update && sudo apt-get install gitlab-ce=gitlab-ce_13.4.6-ce.0
Hit:1 http://it.archive.ubuntu.com/ubuntu focal InRelease
Hit:2 http://it.archive.ubuntu.com/ubuntu focal-updates InRelease
Hit:3 http://it.archive.ubuntu.com/ubuntu focal-backports InRelease
Hit:4 http://it.archive.ubuntu.com/ubuntu focal-security InRelease
Reading package lists... Done
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Version 'gitlab-ce_13.4.6-ce.0' for 'gitlab-ce' was not found

Answer 1

Finally I understand that the problem was related to old PPA. Probably Gitlab team has been updated them, the solution is to manually update PPA with:
curl -s https://packages.gitlab.com/install/repositories/gitlab/gitlab-ce/script.deb.sh | sudo bash
And now update system restart working
ebenedos#fcssrv-git:~$ curl -s https://packages.gitlab.com/install/repositories/gitlab/gitlab-ce/script.deb.sh | sudo bash
Detected operating system as Ubuntu/focal.
Checking for curl...
Detected curl...
Checking for gpg...
Detected gpg...
Running apt-get update... done.
Installing apt-transport-https... done.
Installing /etc/apt/sources.list.d/gitlab_gitlab-ce.list...done.
Importing packagecloud gpg key... done.
Running apt-get update... done.
The repository is setup! You can now install packages.
ebenedos#fcssrv-git:~$ sudo apt update
Hit:1 http://it.archive.ubuntu.com/ubuntu focal InRelease
Hit:2 http://it.archive.ubuntu.com/ubuntu focal-updates InRelease
Hit:3 http://it.archive.ubuntu.com/ubuntu focal-backports InRelease
Hit:4 http://it.archive.ubuntu.com/ubuntu focal-security InRelease
Hit:5 https://packages.gitlab.com/gitlab/gitlab-ce/ubuntu focal InRelease
Hit:6 https://packages.gitlab.com/gitlab/gitlab-ee/ubuntu focal InRelease
Reading package lists... Done
Building dependency tree
Reading state information... Done
1 package can be upgraded. Run 'apt list --upgradable' to see it.
ebenedos#fcssrv-git:~$ sudo apt list --upgradable
Listing... Done
gitlab-ce/focal 13.5.4-ce.0 amd64 [upgradable from: 13.4.3-ce.0]
N: There are 33 additional versions. Please use the '-a' switch to see them.