The two different firmwares are for two different types of 56. The first one is for a "multi-board" controller, the second is for the later released single board. Looking at the software you currently have, you have a multiboard. There is a box on the back lower part of machine that the network cable plugs into?
The problem you are going to run into is the upgrade from x.113 to x.120 is not always just as simple as pushing the file through the web page. If you print a config sheet from copier do you have BIOS version 7.10 or 7.11? If you have 7.10, do not upgrade, you have to do a alt-boot (reload) and upgrade bios in the process. This is normally a billable-upgrade.
