There are 500 unique users in our system and we have created a notification system that will send all the users a plain-text email when there is an update to one of the sections. The system uses swiftmailer and creates an email object and then BCCs the 500 users before sending it.
I just want some reassurance that BCCing 500 users means the server will consider this as sending out 1 email but to a lot of users. I don’t want to run into any email limit restrictions set by my server host.
It will not count as one email. The fact that the content of the message is the same is irrelevant, as you still have 500 recipients. In addition, your host’s email server probably caps the number of BCC recipients per message at a more reasonable value, so I’d be surprised if you could even do this at all. This sort of blast should be sent via individual messages. If your host balks at the volume, you’ll likely have to go to a delivery service like Constant Contact et al.