Custom plugin for php fox and procon for reserved slots

I need a custom plugin script. What i need it to do. Collect information from a custom field ( EA_ ID, or Punkbuster GUID )on my website and implement this into plugin that will update a reserved slot list located on a separate database. Each user that donates towards my costs is rewarded with 30 days reserved slot on all of my servers. At the end of these 30 days, the user will be removed. I would need this plugin to check this list several times an hour to keep it up to date. The plugin will only be accessible via the admin panel that already exists in php fox.