Audience for Informational Emails

We are sending an informational based email next week to communicate some of our support pages being down for maintenance. I typically only send marketing emails to my engaged audiences and I’m not sure if I should send this type of email to the entire list or continue to focus on my engaged list. My concern is that although the information is timely and necessary, sending to the whole list will affect our deliverability scores. 

Overall, hoping someone has some insights on best practices for sending informational emails and what your audience should look like. Thanks!