Ok, I think that for future tech news, you might adapt the following:

The [[$version|new version]] of MediaWiki will be on test wikis and MediaWiki.org from <tvar|date1>{{#time:d xg|13 December|{{#translation:}}}}</>. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:d xg|14 December|{{#translation:}}}}. It will be on all wikis from <tvar|date2>15 December</> ([[$calendar|calendar]]).

But I'm not completely sure, as I found no documentation on the {{#translation:}}, which is documented in the case where you concatenate it to category where it provide "/ar" for Arabic, with a prepended slash. So you should check if is possible to use it as is. If you find documentation about the {{#translation:}}, or a magic word that return the current translation targeted language without a prepanded slash,  please give feedback. In the worst cas, provided that Extension:StringFunctions is provided, you might use sub.

References :

https://www.mediawiki.org/wiki/Help:Extension:Translate/Page_translation_administration#Markup%20examples

https://www.mediawiki.org/wiki/Special:MyLanguage/Help:Extension:ParserFunctions#.23time

The latest tech newsletter is ready for early translation:
https://meta.wikimedia.org/wiki/Tech/News/2016/50

Direct translation link:
https://meta.wikimedia.org/w/index.php?title=Special:Translate&group=page-Tech%2FNews%2F2016%2F50&action=page

I'm planning to send the newsletter on Monday afternoon (UTC), i.e.
Monday morning PT. The existing translations will be posted on the
wikis in that language. Deadlines:
https://meta.wikimedia.org/wiki/Tech/News/For_contributors#The_deadlines

There may be a few more edits by Friday, but the existing content
should generally remain fairly stable. I will let you know on Friday
in any case.

Let me know if you have any questions, comments or concerns. As
always, I appreciate your help and feedback.

//Johan Jönsson
--

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