HTC has begun rolling out the Android 5.0.2 Lollipop update for its various smartphone models.

The update for the HTC Butterfly S, Desire Eye and One E8 was made available to users residing in certain regions but is expected to be released worldwide within the next few weeks.

Through a series of tweets, tech news insider LlabToorFeR revealed details of HTC's Lollipop update rollout, NDTV has learned. According to the tipster, the update was first rolled out for HTC One E8 users in Hong Kong and has a size of 955.27 MB with the ROM version 2.33.708.3.

The update for the Desire Eye and Butterfly S, on the other hand, came out for Taiwanese users and sized at 1009.9 MB and 708.86 MB respectively. The ROM version for the Desire Eye update is 2.19.709.1 while the Butterfly S is 5.16.709.3.

Although the updates were already made available, LlabTooFeR noted that certain HTC models will not receive the bundled Android 5.0.2 Lollipop with Sense 7.0 user interface (UI).

The insider explained that only models with Android 5.1 OS will receive the Sense 7.0 UI. These include the HTC Desire Eye, One M8, One M8s and Butterfly 2, according to International Business Times.

The Android 5.0.2 Lollipop update is expected to become available to other countries in the near future. But since HTC's smartphones are carried by different providers in the U.S., such as Sprint and AT&T, the release dates for the update may vary.

Aside from the abovementioned models, another HTC device that is expected to receive the Android 5.0 Lollipop update is the Desire 816. It was reported in late March that the update for the smartphone might arrive within ne next couple of weeks, Phone Arena reported.

As HTC's mid-range smartphone with a retail price of around $200, the Desire 816 has a 5.5-inch 720p display screen and 1.5 GB of RAM. Its 13-megapixel rear camera is paired with a 5-megapixel front camera. The device runs on a quad-core Snapdragon 400 processor.