There are sources for QPR Beta available, that´s not the problem.
Copy paste from another post in this thread where I already answered the question, why I don´t support dev-previews/betas:
No, I have no plans to support A13 beta or any dev-preview or beta firmware. It will be supported once it´s stable. I don´t have the time, desire and motivation to support it.
It all boils down to the fact that I enjoy doing what I´m doing here, I do it in my free time and share what I´m using myself with others so they can enjoy it with me and I want to release something that´s polished, extensively tested and stable.
Since that questions comes up from time to time:
I´m not comfortable releasing something I´m not running/testing extensively myself with loads of changes compared to the stock base.
I never felt the urge to do beta testing for companies just to run more recent software too.
I don´t have time to test, maintain and build that many compilations, let alone switching between Beta Firmware and Stable firmware on my phone for testing. It´s simply not possible, and I don´t want to release something that´s not extensively tested.
I think sometimes people don´t realize how much time goes into this aspect of my kernels projects alone.
Also try to see it that way:
Merging code updates takes time. Be it linux-stable, f2fs-stable, kernel/common, lrng updates, updates directly from Google or a lot of the features that are descrbied in the OP. Sometimes longer, sometimes shorter.
This kernel is now very very far from the stock base (compared to the other kernels available) as is also reflected in the OP. So while merging code updates will take time as there are many conflicts that need to be solved on my kernel. Even if the branches are somewhat similar I still need a lot of additional time to manage this aspect alone, not to speak of testing on my device to make sure nothing is broken.
There´s no longer just the kernel repo itself to manage. With the introduction of GKI, the kernel is split in several sub repos for different device specific drivers, touchscreen, wifi, uwb, nfc, bt, etc etc. Those needs to be managed too, as well as other repos from the build environment as they´re different between stable and beta.
Powerhal changes need to be monitored and adjusted each month too, as there might be differences between stable and beta as well.
Building takes time. Every compilation, for testing or release purposes takes about 15 minutes. Only building, not adjusting the code. Every release here needs 2 different builds for oriole/raven. Yes I can do something else during the compilation, but it´s still time I need to spend.
No there´s no telegram group. Everything you need is here on XDA. All information is in the first few posts. If you use the search function you´ll find even more I guess.