We’ve been pointing out this was almost certainly going to happen since they launched:
https://androiddev.social/@MishaalRahman/113601522660269275
Why? Android doesn’t have any long term support branches for older versions of the mobile OS. Today’s release of Android 15 QPR1 is the only supported stable release.
All the Tensor Pixels from the Pixel 6 through the Pixel 9 Pro Fold have very similar hardware. They run nearly the same firmware and software. Generational upgrades to the CPU, GPU, SSD, Wi-Fi, cellular, etc. haven’t made them drastically different devices, unlike before Tensor.
One of the main differences was that the Pixel 6 and 7 use the Linux 5.10 LTS branch, Pixel 8 used 5.15 and Pixel 9 used 6.1. However, 6th/7th/8th gen Pixels are moving to the 6.1 LTS branch with Android 15 QPR2. They’ll likely move to a new branch each year after that migration.
Linux extended LTS branch support from 2 years to 6 years, mainly for Android. However, they moved back to 2 years after Google made major improvements to enable easier migrations to new branches. Whether or not other Android devices handle it, Pixels are dealing with it already.
We recently published a thread about the upcoming 6.1 LTS branch upgrade for 6th/7th/8th gen Pixels here:
https://grapheneos.social/@GrapheneOS/113533415116755738
6.6 LTS is used for microdroid virtual machines on the Pixel 6 and later, and they did port the bare metal drivers, but it’s not mature enough yet.
Yearly Android releases receive approximately 1 year of monthly/quarterly updates leading up to the next yearly release. After that point, they aren’t really developed or maintained anymore. Most people confuse monthly security backports to old versions with the monthly updates.
Android Security Bulletin monthly security patches are backports of most High and Critical severity patches to the Android Open Source Project to old major releases from the past ~3 years. The initial release of Android 15 is one of those older releases and receives backports.
These backports do not include the vast majority of the Low and Moderate severity patches. Backports are often done significantly later compared to when they initially ship in the latest monthly/quarterly/yearly OS release. Backports are also not a continuation of the branch.
For example, the last release of Android 14 was a final monthly release for Android 14 QPR3 (3rd quarterly release from June 2024). Android 14 QPR3 was much closer to Android 15 than initial Android 14. Backports they publish for 14 are for the first Android 14 release, not that.
In order to continue support for Pixels on an older branch Android, they’d need to create an LTS branch for it and do much more backporting and other work than they’re currently doing. It is far easier for them to keep bringing them the latest OS releases until their end-of-life.
It was clear they’d likely provide 5 years of OS updates for 6th/7th gen Pixels rather than 3 from the start. Documentation clearly hinted at it by saying they’d provide 5 years of security AND features updates. Many people misinterpreted minimum guarantee as an end-of-life date.
Once 8th gen Pixels were released with the minimum guarantees extended to 7 years of security updates and 7 years of the latest Android OS updates, it was near certain they were going to do 5 years of the latest OS updates for 6th/7th gen. It kept being misreported over and over.
Many years ago, Nexus devices with a promise of 2 years of OS updates and 3 years of security would receive 3 years of both. First non-Snapdragon Pixel, the Pixel C, got half a year support beyond the minimum 3 years despite awful sales. It’s a minimum, not an end-of-life date.
People should plan for 6th/7th gen Pixels not getting more than the promised 5 years of support. However, they could probably extend them to getting 7 years like 8th/9th gen Pixels without much trouble. Main barrier to cheap long term support (Snapdragon) is gone for Pixel 6+.
Since Android 14 QPR2, quarterly releases of Android upgrade to a newer main branch of the OS like yearly releases. Quarterly releases leave the feature flags for upcoming yearly release features disabled. Quarterly and yearly releases have a similar amount of code changes now.
Android 14 QPR3 is far closer to the Android 15 code than the initial Android 14 code receiving Android Security Bulletin (ASB) backports. Android 15 ASB backports are generally going to be much easier to apply to Android 14 QPR3 than the Android 14 ones. Few understand this.
Pixels are essentially the only Android devices shipping monthly and quarterly Android releases. Other vendors use an initial yearly release, apply a year or more of Android Security Bulletin backports and then do a generally very delayed update to a new initial yearly release.
Android 14 was released October 2023. The release in November should really have be called Android 14.0.1 and then Android 14.1 for Android 14 QPR1 in December. Google seemingly doesn’t do this because people would realize how bad updates really are for non-Pixel Android devices.
Instead, they don’t mark the monthly and quarterly releases in a particularly user-facing way so people confuse monthly releases with incomplete monthly ASB backports. Google refers to quarterly releases and app updates alongside them as Pixel Feature Drops in their marketing.