Due to time constraints there will not be a new release on Dec. 31 + with the inclusion of ffmpeg 6.1, there are still some areas that need more testing.

Does that mean that libsvtav1 v. 1.8.0 and also libaom-av1 v. 3.8.0
encoders will be available for testing in the upcoming Cin-GG ?

Because aom version 3.8.0 does not build on Ubuntu 16, at this time, it is unknown which direction it will go.  But it has always been that being able to build CinGG on older systems to include also, 32-bit system, is probably of the highest priority.  This means that aom version 3.8.0 would not be checked into GIT until more is known and maybe not even.  Which means it would not be part of the automatic package builds.