Answering the second question first, ABL is just a rebranding of what used to be called 4GL so it isn't as if one would have a separate tool.
There have been some previous efforts at creating UML from ABL by PSC's consulting group, but these have been limited to the kind of information available from XREF, which has substantial limitations which CallGraph does not have. Also, we will be pulling information from multiple sources.
As to timing, the initial version of the profile is already published and one could start using it right now for hand created entries. We are very interested in people starting to work with the profile so that we can get feedback on completeness and correctness so that this can become a generally used standard. We roughly expect a working version covering the first three stages by fall.