Не может установить более новую версию FreeCAD от PPA

Я пытаюсь установить FreeCAD на своем компьютере (работающий 18.10) и сталкиваюсь с небольшим количеством проблемы с установкой. Я хотел бы использовать последнюю стабильную версию от ppa:freecad-maintainers/freecad-stable, поскольку версия в основных репозиториях устарела и имеет несколько ошибок на запуске. Проблема, даже после добавления PPA к моим источникам, apt все еще устанавливает версию из официальных репозиториев.

Это - мой вывод от выполнения sudo apt update

Hit:1 http://download.virtualbox.org/virtualbox/debian cosmic InRelease
Hit:2 http://us.archive.ubuntu.com/ubuntu cosmic InRelease                     
Get:3 http://us.archive.ubuntu.com/ubuntu cosmic-updates InRelease [83.2 kB]   
Get:4 http://security.ubuntu.com/ubuntu cosmic-security InRelease [83.2 kB]    
Hit:5 http://ppa.launchpad.net/freecad-maintainers/freecad-stable/ubuntu cosmic InRelease
Get:6 http://us.archive.ubuntu.com/ubuntu cosmic-backports InRelease [74.6 kB] 
Hit:7 http://ppa.launchpad.net/js-reynaud/kicad-5/ubuntu cosmic InRelease      
Fetched 241 kB in 1s (343 kB/s)                                                
Reading package lists... Done
Building dependency tree       
Reading state information... Done
All packages are up to date.

Таким образом, Вы думали бы последние пакеты от специалистов по обслуживанию FreeCAD, стабильный PPA должен быть доступным, правильно? Однако вывод apt policy freecad

freecad:
  Installed: (none)
  Candidate: 0.16.6712+dfsg1-3build1
  Version table:
     0.16.6712+dfsg1-3build1 500
        500 http://us.archive.ubuntu.com/ubuntu cosmic/universe amd64 Packages

Если это полезно, вот мой /etc/apt/sources.list

# deb cdrom:[Ubuntu 18.10 _Cosmic Cuttlefish_ - Release amd64 (20181017.3)]/ cosmic main restricted

# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://us.archive.ubuntu.com/ubuntu/ cosmic main restricted
# deb-src http://us.archive.ubuntu.com/ubuntu/ cosmic main restricted

## Major bug fix updates produced after the final release of the
## distribution.
deb http://us.archive.ubuntu.com/ubuntu/ cosmic-updates main restricted
# deb-src http://us.archive.ubuntu.com/ubuntu/ cosmic-updates main restricted

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team. Also, please note that software in universe WILL NOT receive any
## review or updates from the Ubuntu security team.
deb http://us.archive.ubuntu.com/ubuntu/ cosmic universe
# deb-src http://us.archive.ubuntu.com/ubuntu/ cosmic universe
deb http://us.archive.ubuntu.com/ubuntu/ cosmic-updates universe
# deb-src http://us.archive.ubuntu.com/ubuntu/ cosmic-updates universe

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu 
## team, and may not be under a free licence. Please satisfy yourself as to 
## your rights to use the software. Also, please note that software in 
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://us.archive.ubuntu.com/ubuntu/ cosmic multiverse
# deb-src http://us.archive.ubuntu.com/ubuntu/ cosmic multiverse
deb http://us.archive.ubuntu.com/ubuntu/ cosmic-updates multiverse
# deb-src http://us.archive.ubuntu.com/ubuntu/ cosmic-updates multiverse

## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb http://us.archive.ubuntu.com/ubuntu/ cosmic-backports main restricted universe multiverse
# deb-src http://us.archive.ubuntu.com/ubuntu/ cosmic-backports main restricted universe multiverse

## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
# deb http://archive.canonical.com/ubuntu cosmic partner
# deb-src http://archive.canonical.com/ubuntu cosmic partner

deb http://security.ubuntu.com/ubuntu cosmic-security main restricted
# deb-src http://security.ubuntu.com/ubuntu cosmic-security main restricted
deb http://security.ubuntu.com/ubuntu cosmic-security universe
# deb-src http://security.ubuntu.com/ubuntu cosmic-security universe
deb http://security.ubuntu.com/ubuntu cosmic-security multiverse
# deb-src http://security.ubuntu.com/ubuntu cosmic-security multiverse

# This system was installed using small removable media
# (e.g. netinst, live or single CD). The matching "deb cdrom"
# entries were disabled at the end of the installation process.
# For information about how to configure apt package sources,
# see the sources.list(5) manual.
deb [arch=amd64] http://download.virtualbox.org/virtualbox/debian cosmic contrib
# deb-src [arch=amd64] http://download.virtualbox.org/virtualbox/debian cosmic contrib

И вот вывод ls -al /etc/apt/sources.list.d

total 24
drwxr-xr-x 2 root root 4096 Dec  5 10:33 .
drwxr-xr-x 6 root root 4096 Dec 16 11:03 ..
-rw-r--r-- 1 root root    0 Dec  5 11:02 elmer-csc-ubuntu-ubuntu-elmer-csc-ppa-cosmic.list
-rw-r--r-- 1 root root    0 Dec  5 11:02 elmer-csc-ubuntu-ubuntu-elmer-csc-ppa-cosmic.list.save
-rw-r--r-- 1 root root  172 Dec  5 11:02 freecad-maintainers-ubuntu-freecad-stable-cosmic.list
-rw-r--r-- 1 root root  172 Dec  5 11:02 freecad-maintainers-ubuntu-freecad-stable-cosmic.list.save
-rw-r--r-- 1 root root  140 Dec  5 11:02 js-reynaud-ubuntu-kicad-5-cosmic.list
-rw-r--r-- 1 root root  140 Dec  5 11:02 js-reynaud-ubuntu-kicad-5-cosmic.list.save

Если существует что-нибудь, что могло бы быть полезно, который я забыл обеспечивать, сообщите мне. Заранее спасибо за любую справку!