The update is currently in the process of being tested on the device and Android 4.3 is penciled in for a late September rollout. Considering that Sunday starts the third week of the month, we would expect the update to be coming any day now. And if you live in the U.S., no worries. As we told you earlier this month, all signs point to the update coming to the U.S. with Sense 5.0. This also is expected to take place in a matter of weeks.
After coming to Canada and the U.S., the international version of the HTC One will be next in line to receive Android 4.3. One big difference however, is that the overseas HTC One will be receiving Sense 5.5 along with its Android 4.3 update.
source: TELUS via MobileSyrup