Hi Dave,
Start now. Treat these 8 people like gold: they subscribed because they genuinely like your message. Start sending them things once or twice a week, maybe use content you already have with links to the full story, or go a little deeper for them.
Definitely promote your e-mail list more. After every article and in your bio. I had a quick look at your profile and one article, and didn’t even see where I can subscribe.
I talk about these things in my newsletter. It’s about one-person business success, and you’re welcome to join here: https://1personbusiness.substack.com/
In any case, thank you for reading and for your comment ❤️