Digital Direct has a "throttling" process on emails being sent that is engineered for creating maximum deliverability. When you begin, your account has zero email reputation. Our job is to, as quickly as possible, create a positive reputation so you have a direct communications channel to get your emails to your prospects. That's what the throttling drip process is designed to accomplish. Here's how it works:
Whenever you send to a "new" email, that hasn't been sent before, we spread out those emails over a 7 day period.
Then, after the first email is sent, those recipients get sorted into two "buckets": 1) Readers; 2) Non-Readers.
When your subsequent emails get sent out, the "Non-Reader" file gets throttled over a 24 hour period. The "Reader" file gets sent immediately.
The good news about this approach is it works.
The downside is you don't have exact precision as to when emails are sent, except for the reader file, which doesn't have any throttles placed on it.