pfSense 2.4.3_1 upgrade might fail at first attempt

If you have not upgraded your pfSense to the latest version (read release announcement for details on what was fixed: 2.4.3_1 released 14 May 2018), just be aware that there might be a hiccup during the upgrade. The upgrade fails with the interface showing the following:

My pfSense instance gave the above message and also the following in the system log:
May 21 19:20:10     php-fpm     61392     /index.php: Successful login for user 'admin' from: 192.168.34.12
May 21 19:22:33     check_reload_status         Syncing firewall
May 21 19:22:35     pkg-static         pfSense-upgrade upgraded: 0.42 -> 0.45
May 21 19:22:48     check_reload_status         Reloading filter
May 21 19:22:48     check_reload_status         Starting packages
May 21 19:22:49     php-fpm     61392     /rc.start_packages: Restarting/Starting all packages. 

I opened another tab in the browser and checked the pfSense GUI, and it still showed the old version. As per the release announcement, run the following command to refresh repository configuration:

pkg-static clean -ay; pkg-static install -fy pkg pfSense-repo pfSense-upgrade

and attempt an upgrade again. The second attempt has been reported to be successful most of the times. The issue is logged as a bug already.

Note: As always, before upgrade, take a backup of your configuration. Also, in case you are running pfSense in a virtual environment, take a snapshot before upgrade so that you can easily revert in case something happens that cannot be fixed.