Rogers Wireless has released the Windows Mobile 6 upgrade for the HTC S621, its version of the HTC S620 (Excalibur). Great news! Windows Mobile 6 upgrade is now available for the HTC S621. Better yet, it’s easy to upgrade and the software is free! Now you can take your smartphone’s capabilities to the next level – saving you even more time and becoming even more productive while on the go.
This upgrade applies only to the Rogers Wireless version of the Excalibur and should take about 25 minutes.
Note that this a full ROM update and all user data and programs as well as partnership information will be erased in the upgrade process. Also make sure you read all the instructions and prerequisites before attempting to flash your ROM.
Source: Smartphone Thoughts