And just an observation on historical patterns: releases often linger for a very long time in the "should be ready to go out in a couple of weeks" state. I've found that it's usually the case that he has to be in the "just one or two more bugs" stage before it's likely to be a couple of weeks. Not a criticism; just the way things are.
The other datum is that Steve seems to have had a lot less time for Aurora for the last year or two, which will also stretch out the ETA.
So my advice would be not to wait for a new release unless Steve is saying he's moments away from shipping. In addition, just because Steve puts out a new release doesn't mean you need to take it - you can continue to play your campaign with the version you started it with.
This would be OK normally, but in the case of 6.30 it's a "beta" and Steve stated that:
"Therefore I've decided to release v6.30 as a beta. This will probably be less stable than normal"
In practice it means that if you wait with major campaigns until 6.40 you also get the features of 6.30 a bit better tested. Combining the lists of changes from 6.30 and 6.40 you get a pretty impressive list.
Since 6.30 BETA has been out for quite some time now I hope that Steve can find a few spare days during Easter to focus on testing, bug fixing and release 6.40 in the current state it is in. Quite a big list of new stuff (especially so including the 6.30 list).