The very ballparkish figures I have seen preliminary suggested (vague enough?) is
May 7 - Release Alpha1
+ Includes undertow, some ee7
June 11 - Release Beta
+ more progress on EE7
July 11 - Release CR1
+ EE7 feature complete
July 25 - Release CR2 if needed
(Hopefully TCK 100% by this date)
August 8 - Release Final
It's impossible to say what issues you might run into (I doubt they will be that huge) but you might want to try 7.2.0.Final/EAP 6.1A first as it's somewhere in the middle and should give you an indication where stuff is headed.
Can you please tell me where I would download the 7.2.0.Final/EAP 6.1A from?