Why? Because April 2010 was a turning point for file hosting:
This refers to a specific version of RapidLeech , a popular open-source PHP script used to transfer files between various file-hosting services (like RapidShare, MegaUpload, Hotfile, etc.) and a user's server. The "PlugMod" and "Eqbal" designations refer to specific community modifications that added features, fixed bugs, and updated the "plugins" used to download from file hosts.
This specific revision optimized how the script used CPU and RAM, allowing users to run it on cheaper shared hosting plans without getting banned.