The file seems to be created by a script called extract_strings.py and is missing several strings from new or modified command line switches. This needs to be updated, to be able to create a full translation of the client. It seems like @laanwj did this the last time.
I would suggest, that there will be defined a standard as to when this file gets updated. At least the final RCs of a new version should include a complete translation and this takes some time for the translators, so the english source files need to be pushed to transifex early (the latest, if a new version is feature-complete). I as a native german speaking person think it's a great benefit for all Client users, if it's completely presented in the native language, so that should get some more love.
