Sean, purging non-openers in 30 days might be excessive. Maybe that’s how I lost touch with you last year.
My email is set not to allow ET to “phone home” to prevent additional spam. You are one of 5 people whose emails I always open and read, no matter what! I lost track of you last year and thought you discontinued your faith-based coaching calls. It wasn’t until last week I discovered you were still at it.
Very many people have spam-protection that prevents their emails from reporting delivery to minimize spam.
Please consider that when canning email addresses. Don’t throw the baby out with the bath water…