Since 2019-03 (two issues ago), Tech News MassMessage delivery to he.wikipedia.org fails in wikitext.
* In wikitext in Hebrew if the target is not on he.wikipedia.org [[ https://he.wikisource.org/w/index.php?diff=881760 | example from Hebrew Wikisource ]]
* On he.wikipedia.org if the target is a Flow page ( [[ https://he.wikipedia.org/wiki/%D7%A0%D7%95%D7%A9%D7%90:Usq69mhn9ke21t27 | example ]])
* For surrounding entries on the target list if they are not on he.wikipedia.org
See https://meta.wikimedia.org/wiki/Global_message_delivery/Targets/Tech_ambassadors for the target list.
See https://meta.wikimedia.org/wiki/Talk:Tech/News/2019/03#A_bot_problem for the initial report.
I have only done a manual check of other targets for 2019-04, but they have all been successful deliveries. Theoretically this could be part of a larger problem and I just haven't found the other unsuccessful deliveries, but then I've been very unlucky.