We just released 4.4. Beta, please find it on our Github repo. With this release we provide major improvements in reliability for the lwIP TCP/IP stack as well as lots of bug fixes. Please check our backlog on the older Codeplex issues list, and if you find that any issue you care about has not been fixed yet , please re-open the issue on the Github repo and we will eventually get to it. We do intend to move all active issues to Github, so we appreciate you giving us the right cues.
Next stop is RTM by end of August, or slightly after.