Want to let them know? They've turned off issues on the GitHub repository, they have no Twitter account, and you have to register for Assembly even to raise a bug.
Want to send feedback? There's a form at the bottom of formspree.io and we've got people in the community that are now responding to those customer service inquiries.
Several have asked about the 10m delays. We switched email providers so we could improve our email deliverability and spam filtering. But the new provider is throttling us while they get a sense of our email traffic. I've been told that it should be back to normal soon. These are growing pains.
Frankly I'm pleasantly surprised to see the project gaining momentum. The alternative would have been to shut it down.
The fact that Brace/Formspree allocate so many points to customer service inquiries on Assembly sounds like you're being inundated with questions that could be managed in a more open fashion?