Hello @AmandaT784 ,
We haven't received any reports of server issues on our end, and I was able to get the test email to arrive right away.
I did notice that this was in the feedback queue and that the scheduled email is Legacy. Is that the email you've had trouble doing test sends of? Was it attempted in the evening? If so, we've heard reports of some customers having issues with the legacy editor in the evenings, but we're not able to recreate said issues on our end.
If that's all the case, would you be able to provide some of the following info: