Here's information on the latest 8820 OS. You can use ANY 8820 OS on ANY 8820 regardless of carrier. http://www.blackberryforums.com/gene...e-english.html
To get BBMaps to show up you'll need this: How to get BBMaps to show up your device? - BlackBerryFAQ
It's easy to do when you're upgrading software.
You can also use Google Maps