I also got a critical error after updating earlier today.
I should also point out that not ALL subscribers get duplicates, but most do.
1. 20 subscribers
2. Nothing is in the CC or BCC fields. The “Send To” field is set as “Subscriber”
3. About 20,000/month and 900/day.
4. No.
I’m experiencing the same issue after upgrading last week. Subscribers are getting 2 emails, consistently. I use the email log plugin to monitor this.
Nothing is set in the CC field. We don’t use any other notification plugins.
