05-20-2013 03:23 PM - edited 05-20-2013 03:24 PM
Hi and Welcome to the Community!
Please refer to this official download portal as you proceed. It is sorted first by carrier -- so if all you want are the OS levels your carrier supports, your search will be quick. However, some carriers are much slower than others to release updates. To truly seek out the most up-to-date OS package for your BB, you must dig through and find all carriers that support your specific model BB, and then compare the OS levels that they support.
With the proper tricks, you can use any OS package from any carrier as long as it's for the exact model number BB.
Good luck and let us know!