[arch-general] Why did kernel packaging become slow?

[Abderrahman Najjar]

​The kernel package (linux) is constantly out of date, both in Testing &
Core.

Whenever a version is pushed in kernel.org, the previous stable will be
still in testing. And then the (old) stable version gets pushed to core,
and the next one in testing will be already old (because it's the latest
stable). Such as the case right now (Core=4.5.1, testing=4.5.2. Stable on
kernel.org=4.5.3)

Is there a reason for such delay?