Repeat notifications from private posts

Starting at about 6:08am (Australian eastern daylight time) through to now, I have received 13 emails saying "There's a new comment on a limited post in diaspora* for you to check out." I've checked. There was only one new comment, made about three hours ago (roughly when the emails started), yet the notifications continue to come. All of them relate to the exact same post (and, presumably, comment.)

This is on diasp.org, where I am registered; the original poster is also registered on diasp.org (so it doesn't appear to be related to federation at first glance).

The issue also refreshes the notification on the pod if it's unread, or creates a new notification if it has been marked as read.

If there is anything further you need to diagnose this issue, please don't hesitate to ask.