Battery-draining bugs have reportedly delayed the full rollout of Google’s Android 5.0 Lollipop.

The next-gen operating system launched on Monday with the Nexus 9 tablet, and was expected to hit the Nexus 4, 5, 7, 10 and Google Play Edition devices shortly thereafter. But thus far, Nexus owners are still waiting.

Some reports are pointing the finger at a problem with the beta version of Lollipop on Nexus 5 that caused a severe battery-drain issue. Google acknowledged the problem in a forum thread(Opens in a new window) on Wednesday, saying that the company was “aware of an issue affecting Nexus 5 users running Android 5.0 which causes significant ‘Miscellaneous’ battery usage while Wi-Fi is enabled.”

Google later issued a fix. But the bug apparently prompted the company to delay the full Lollipop rollout to other Nexus devices. Nexus users with KitKat will have to wait until Nov. 12 for a Lollipop update, according to ZDNet(Opens in a new window).

Google declined to comment further. On Twitter, the @GoogleNexus(Opens in a new window) account told a Nexus 7 user that “the Android 5.0 Lollipop update is delivered over-the-air to your device automatically and should arrive in the coming weeks.”

Previewed at I/O and officially unveiled last month, Android 5.0 Lollipop makes it easier to pick up where you left off—listening to music, scrolling through photos, utilizing favorite apps, even entering search queries.

It also comes with multiple user accounts and guest user mode, as well as default encryption and additional notification controls.

Most notable, perhaps, is Android’s new material design feature, which provides the same user interface across devices. A number of apps—including The Wall Street Journal, Tumblr, and Buzzfeed—have integrated the upgraded design function into their framework.

Early adopters who picked up the new Nexus 9 tablet on Monday are among the first to have a go at Lollipop. The 8.9-inch slate comes with brushed-metal sides and a separate, magnetic keyboard folio.

Rumor has it that Samsung Galaxy S5 owners may soon get a taste of the new OS, which is reportedly expected to reach Samsung’s flagship handset in December.

It is also slated to arrive early next year on the entire Sony Xperia Z series line, starting with the Z Ultra Google Play Edition.

For more, see PCMag’s Hands On With Android L, and our lineup of The 10 Coolest Features in Android L in the slideshow above.