You might be wondering what is keeping the CDK 1.3.1 and 1.2.4 releases. And right you are. When we look at Supernightly, we get a clue (BTW, I hope the EBI nodes will join soon too):
mostly because of ioformats not being tested in 1.2.3 and most of the fails caused by a bug in the test, not in the code. But that still leaves 20 other failing tests. Mostly related to known bugs, and for some problems patches are actually available.
These last 22 we also see in the differences between 1.3.0 and 1.3.1 (while not yet released, called 1.3.0.git). That's because the ioformats modules is not tested in that branch either, pending a new merge with the cdk-1.2.x branch.