Today, all ZENworks update processes include rebuilding deployment packages on every primaries for every platform.

An upgrades from 11.3.x to 11.4.2 takes three rebuilds: one for 11.4.0, one for the pre-req and one for 11.4.2.
This causes unnecessary primary server load, longer upgrade time for the engineers/sysadmins and additional possibilities of failure (if the admin is not patient enough during rebuild).

An ultimate solution is to have an option in the upgrade process (either GUI or command-line one) to just skip the rebuild of deployment packages.
In the above case, 11.4 and prereq could have been run with that option, while 11.4.2 could have been run normally resulting in one rebuild process.
In case of the option used, the old packages can be just removed, so the admin/engineer knows he/she needs to recreate deployment packages during next update or manually.