The hacker made the announcement on Twitter earlier today:
Thanks to everyone who are dumping iPad kernels. It helps a lot. It speeds things up with the 6.1.3/.4 jailbreak. (A lot).
A definite ETA is before 2014. Please also be patient. We are all trying to get things done as soon as possible.
As usual, you can follow iClarified on Twitter, Facebook, Google+, or RSS to be informed of the latest updates.