Google is reportedly gearing up to release the long-awaited Android 6.0 Marshmallow on Sept. 29. This major OS version will apparently be unveiled alongside the next iterations of the Nexus smartphones dubbed LG Nexus 5X and Huawei Nexus 6P. Meanwhile, a new report said that many Android OEMs, including Samsung, are looking forward to the new OS debut to plan firmware updates for their respective devices.

Sam Mobile, citing a Korean source said that Samsung is apparently packaging a "major" firmware update for the recently released Galaxy S6, Galaxy S6 Edge, Galaxy S6 Edge+ and also the humongous phablet Galaxy Note 5. It is worth noting that all the aforementioned devices are running on Android 5.1.1 Lollipop. Therefore, it goes without saying that the next major update is very likely to be the Android 6.0 Marshmallow.

Even though the major update is believed to be Android 6.0, the same site has stated that it cannot confirm the OS version at this point. Apart from the handsets released in 2015, the Galaxy Note 4 will apparently be updated to Marshmallow in the future.

Google released the first Android M developer preview version in May. This preview build apparently came with a new “dark UI theme.” Since the new theme came unexpected, many apparently thought that the search giant has finally brought in the much-appreciated dark theme to its Android platform. But as it turns out, the dark UI theme will not be part of the final build of Android 6.0 Marshmallow, according to Phone Arena.

Notably, Google reportedly removed the dark theme from the second and third Android M developer preview builds. However, developers were hoping to see this option in the final build of the upcoming firmware. Although, the search giant has not officially announced the removal of the dark theme, details ferreted out of Google Issue Tracker confirmed that there would be no dark UI theme when Android M releases next week.