I wanted to migrate from Aegir 0.4-alpha8 to 0.4-beta2. I tried the upgrade a few times with no luck. I am assuming that was due to missing components on my Gentoo system. So, I just built a new Debian Box and installed 0.4-beta2.
Attached is the documentation I used to migrate platforms and sites. This was written inhouse for staff to use to migrate about 40 sites.
Perhaps it will be of some help to others.
A big THANKS to the folks on the IRC channel.