Firstly, I am afraid that, since it has not been possible to reproduce the desyncs except on the server (for reasons that remain unclear), the only way of attempting to diagnose the problem is to continue to run the server, try painstakingly to observe patterns, make small changes to the code and run it again to see whether there is any difference.
Secondly, there are a number of significant projects that have yet to be started, let alone completed, in advance of the next major version, so that is likely to be some time away (and could be delayed very greatly if the desync issues take a long time to resolve).