We can only assume that with the upcoming announcement of the All New HTC One that the phone will not only run the latest version of Android, but will most likely sport the latest version of Sense UI as well, which is supposed to be Sense 6.0.
Assuming that is true, what about older devices? When will they receive the update to Sense 6.0? Based on a video that was leaked earlier, Sense 6.0 was spotted running on the HTC One from back in 2013, suggesting that the latest UI could be arriving for the device. Now thanks to a recent leak by @LlabTooFeR, it shows an alleged roadmap belonging to HTC that details when and which devices would receive the update.
As you can see in the screenshot above, it looks like the HTC One, the HTC One with dual SIM, the HTC One Max, the HTC One Mini, and the HTC Butterfly S will all receive the Sense 6.0 update. However the HTC One will be the first to receive it as its release has been estimated to be between May-June. The rest of the phones will receive the update in June-July, assuming that everything goes according to plan.
The yellow boxes as per the legend suggests that the update is currently undergoing testing, so a May-June release does seem plausible, especially if the All New HTC One is expected to go on sale before that.
We have no way of verifying this leak but @LlabTooFeR has been pretty reliable in the past when it comes to leaks, perhaps there might be some truth in it. Either way we’ll be keeping our eyes peeled so do check back with us at a later date for the details.