I have a question about how to update context modules.  

In earlier correspondence

Question:  I am still having a problem with...[the letter module]
Answer:  This is now fixed...

I use a context installation managed by ubuntu/apt-get from the Personal Package Archive ppa:reviczky/context-daily (https://launchpad.net/~reviczky/+archive/context-daily). The current version is:

How is it possible to (1) tell which version of a module is installed? (2) update a module to the latest version?

Because I use the PPA version, I have not used first-setup.sh.  I have only a limited understanding of where the context supporting material is maintained.

Thank you very much for your guidance.

Best,
Michael

PS Thank you very much for the guidance on the correspondence documentation and the reference line alternatives in the letter module

> BTW are the values for the "alternative" key ("example", "e", "c", etc.) documented somewhere?

You can look at the predefined arguments in the old manual which is available online: https://bitbucket.org/wolfs/correspondence/downloads.