We can't wait too much, because the image decides which file to open, so we can't change it after the release. IIRC Andreas had the idea to create a new sources file for every release, but I may be wrong. I found something that is related to this:
http://lists.squeakfoundation.org/pipermail/squeak-dev/2010-April/148026.htm...
Thanks. So, by my understanding, if we wait to do the condense as one of first steps for 4.3, then the "4.2 release" can be present itself in terms of its predecessor. I have really enjoyed having that during 4.2 and think it's relevant even after release; it seems good to keep delta's with the prior version in each release, especially since it's not very costly.
Also, the sources file contains the license at the beginning. The date there is 2010. I'm not sure if it's a problem or not.
That is only an old, incidental copy of the license, not the official statement about license from Squeak.