There are many blogs and resources that you can follow to learn more about Deliverability, the following list is not exhaustive but should give you a good start:
- Spam Resource: All Things Deliverability
- Blog – Word to the Wise
- Blocklist Resource (dnsbl.com)
- EmailKarma.net – It’s not the size of your list, It’s how you use it!
- Blocklist Resource (dnsbl.com)
- Deliverability Defined | Podcast on Spotify
- SMTP Error Codes in the Wild | SMTP Field Manual
In addition, the EmailGeeks Slack community includes an #email-deliverability channel dedicated to discussion of deliverability that is a great place to ask questions, apply at https://email.geeks.chat/.