I sent a series of emails to different geographical regions yesterday and noticed that they all had a huge open rate of 100%. When I look at the email send dashboard I can see that the delivery rates are really low (about 20%) and the total delivery seems to match that of the opens.
I've sent to these smart lists before where the open rate was roughly 20% and the delivery rate was about 95%. There have been no changes to the filters within the smart lists.
Does anyone know what might be the problem here?