Just noticed 10.10.4 pre-release is there, dated April 27.
Hang on tight 
As for XCode 6.4, I just hope it will not break iOS again.
Wife’s just finished testing our apps with it and so far, the only issues she can find are some Cardob apps are no longer accepting drag and drop of files, while some are…
Carbon? 
I wish Xojo would publish what is safe ASAP after Apple makes releases available. The release say you need at least X, but we need to know that X + 1 is ok too.