We are still collecting information, but several users of the German-language Wikipedia are reporting that they have not received any Echo notification that one of their articles was linked since end of June. ([[https://de.wikipedia.org/w/index.php?title=Wikipedia:Fragen_zur_Wikipedia&oldid=179320762|permalink to current state]][[https://de.wikipedia.org/wiki/Wikipedia:Fragen_zur_Wikipedia#Mitteilung_%C3%BCber_neue_Verlinkung|live link (will be archived)]])
The two users who have confirmed they stopped receiving notifications are [[https://de.wikipedia.org/wiki/Benutzer:Hoefler50|Hoefler50]] and [[https://de.wikipedia.org/wiki/Benutzerin:L%C3%B3melinde|Lómelinde]]. We are still trying to find out if this affects all users or just a certain group.
Since the change to global preferences falls into this timeframe, it might be that this Echo problem is related.