It has been quite soon after the release of Android 4.0.4 update for the top smartphone One X, HTC doesn’t want to let down their mid-range smartphone users, One S. Within the next few hours, HTC will push the update to your phone directly which is in OTA method so you don’t need to connect or use PC to update.
The total update size is about 157MB including the Android 4.0.4 Ice Cream Sandwich and Sense v4.1. If you can’t find the update now in your regime, you better wait a few more days.
How to update HTC One S to Android 4.0.4
Since it is OTA update, you don’t need to do anything much. The total update size is about 157MB so make sure that your device is connected to a WiFi network. The go to Settings -> About -> Software Updates.
What we are waiting now is the update to Android 4.1.1 Jelly Bean.