For me in the update limbo-state the pkcon update just complained Failed to contact PackageKit: Could not connect: Connection refused and because there was no Internet-connection, version --dup would wait for eternity in REFRESHING CACHE AND DOWNLOADING PACKAGES.
But zypper worked and could finish the incomplete dist-update, so maybe it can help you also. Install at least zypper from these links and if it complains about missing depencies, download install them as well:
https://releases.jolla.com/releases/3.4.0.24/jolla/armv7hl//core/armv7hl/zypper-1.14.6+git4-1.5.1.jolla.armv7hl.rpm
https://releases.jolla.com/releases/3.4.0.24/jolla/armv7hl//core/armv7hl/augeas-libs-1.12.0+git2-1.5.1.jolla.armv7hl.rpm
https://releases.jolla.com/releases/3.4.0.24/jolla/armv7hl//core/armv7hl/readline-8.0+git1-1.4.1.jolla.armv7hl.rpm
Copy them to you phone, if you phone has encrypted /home-partition command following (other if no enctyption, skip to next step):
cryptsetup luksOpen /dev/sailfish/home whatever
mount /dev/mapper/whatever /rootfs/home
Then use chroot /rootfs and install zypper with rpm -Uvh /path/to/the/zypper-rpms/*.rpm -command.
Now command following commands:
mv /var/cache/zypp /var/cache/zypp-old
ln -s /home/.pk-zypp-dist-upgrade-cache /var/cache/zypp
su
zypper dup
rm /var/cache/zypp
mv /var/cache/zypp-old /var/cache/zypp
and then reboot your phone to see if it worked.